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By M. Keevy, K. Hackney

Centrifugal slurry pump station and deposition sites are a common feature of many mines and mineral processing plants. Yanacocha Mine has completed the design of a pump station consisting of two trains of four pumps each. A number of trade-off studies was conducted to optimize the pump station design. The most significant of these was determining the drive types for the slurry pumps. The pump station duty can vary considerably due to the number of deposition points round the disposal site. The standard solution to this problem on a multi-stage pump train is to install one pump with a variable speed drive to control the pump station output by varying the speed of this pump and stopping and starting other stages. However, there are a number of negative impacts associated with this approach. These include head losses through pumps that are stationary or ?wind-milling?, different wear life on pumps that are running and pumps that are stationary, and slower response to the control system with the possibility of hunting. The use of variable speed drives on all the pumps was considered as an alternative to the standard solution. The factors considered in comparing these options were the control and operational differences, the pump efficiencies and absorbed power, the expected pump wear life, the impact on pump maintenance and the cost of the drive options. For this project the option of using all variable speed drives was selected. The paper presents the following aspects of the study: ?Description of the various options investigated. This includes a discussion on the required duty and the drive options. ?Technical comparison between the options. ?Description of the factors influencing pump performance and life.

Jan 1, 2007

1. New Publications Tin and its uses no. 140. Greenford (England), International Tin Research Institute, 1984. Catalogue. English translations of German standards 1984. Berlin, Beuth Verlag GmbH, 1984. Mining and mineral processing operations in Canada 1983. Ottawa, Canadian Government Publishing Centre, 1984. $6.00. Canadian mineral deposits not being mined in 1983. Ottawa, Canadian Government Publishing Centre, 1984. $6.00. 2. Mintek Publications Report M42D The recovery of tantalite and cassiterite from a bulk sample of pegmatite supplied by Falconbridge Explorations Limited. (First issued 1982.) Report M46D Tests on the nature and reduction of the chlorine in fluorspar concentrate from the western Transvaal. (First issued 1982.) Report M58D An electrochemical process for the recycling of tungsten carbide scrap. (First issued 1982.) Report M59D Testwork on samples of oxidized ore from the Potgietersrus Prospect. (First issued 1982.) Report M60D The production of electrolytic manganese dioxide from furnace sludge. (First issued 1983.) Report M64D Isotope-source neutron-activation analysis for the determination of manganese in bulk samples. (First issued 1982.) Report M128 The determination of cyanide in hydrometallurgical process solutions and effluents by ion chromatography. Report M132 Mineralogical parameters influencing the acid-bacterial leachability of low-grade nickel ores. Report Ml34 The NIMROC reference materials: revised values for thorium, yttrium, lanthanum, and the rare-earth elements. ReportM140 The effect of physical and chemical factors on the corrosivity of a synthetic mine water. Report Ml44 The development of standard procedures for the evaluation of magnetite for use in heavy-medium separation. Report M145 A preliminary study of the mineralogy of the nickel occurrence at Mabilikwe Hill, northern Transvaal.

Jan 1, 1984

By Noel C. Joughin

In making judgements on tolerable levels of risk in industry, and in all spheres of life, it needs to be understood that every action gives rise to risk. Without risk, nothing can be done. Without risk, no economy could be advanced. There is a strong tendency to emphasize the risk at work, but persons who are not working are exposed to a different set of risks. Often persons who are not working face greater risks than persons who are working. Simply, in being alive, one is exposed to the risk of an accident, the risk of contracting a disease, and an extremely diverse variety of other risks. According to the Health and Safety Executive of the UK, it is not possible to have a state of zero risk, because ?a state of zero risk does not exist?. Because zero risk is a physical impossibility, it is not possible to design for a state of zero risk in all engineering design. While the strategic target of achieving zero risk is laudable it does not provide any practical guidance to engineers as to what acceptable limits of risk should be. This causes a significant and real problem in the design for and the management of risk. Without meaningful guidelines, engineers, managers and the authorities often find themselves in disagreement. Thus, it has become essential to establish criteria for tolerable levels of risk and unacceptable levels of risk in order to design and manage engineering systems properly.

Jan 1, 2011

By J. H. Zietsman, W. J. Leipoldt

"To be able to responsibly develop a multiphysics model of the steel belt sintering (SBS) process used to sinter chromite fines, it is important to have a comprehensive understanding of the process. This understanding was gained through a site visit, observation of the process in operation, and interaction with the operators. Material characterization will also reveal much about the process that is not yet fully understood. A well-defined and representative mass and energy balance will also give valuable insight into the process. The plan for the multiphysics model aims to combine a computational fluid dynamics (CFD) model with a discrete element method (DEM) model.To obtain a more accurate mass and energy balance representation of the SBS process, it was decided to develop a dynamic distributed parameter model of the mass and energy balance. This model will be used to gain better understanding of the SBS process so that a more complicated multiphysics model can be developed later. The reason for this is because the SBS process is very dynamic, with a large temperature distribution throughout the length of the process. In its current state, the mass and energy balance model is capable of handling solid and gas material packages and exchanging heat between these packages where they are mixed, and is able to model the heating of the gas by burning CO gas. The next step in the development of the model will involve enabling it to handle evaporatoin of liquid water, burning of solid carbon in the pellets, reduction of iron oxide in the pellets with the CO gas formed from carbon combustion, and then oxidation of the reduced iron in the oxygen-rich cooling zones."

Jan 1, 2014

By Y. Wang, S. Sridhar, B. Coletti, G. N. Shannon, S. Vantilt

The final removal of inclusions in the ladle, tundish, and mold in a continuous casting process involves the kinetic steps of liquid film drainage, interface rupture, and absorption of the inclusion into the overlaying molten slag. During this process, oxide inclusions can undergo chemical reactions with the slag. This paper presents recent results on imaging the slag/steel interface and elucidates the evolution of Al2O3and Al2O3-CaO inclusions during their separation from the steel and on their incorporation into the slag. Experimental results, obtained through a Confocal Scanning Laser Microscope, are compared with thermodynamic predictions.

Jan 1, 2004

By J. A. L. Napier

SYNOPSIS Many tabular mining problems can be modelled effectively by displacement-discontinuity techniques, which can be extended directly to represent fracturing on discrete planes and movements on planes of weakness. This paper presents a unified method for computing the energy changes that occur when multiple discontinuities intersect and are extended incrementally. It shows how this method can be used to deduce energy-release information for standard layout problems and, in addition, how the technique can be incorporated in numerical procedures based on the displacement-discontinuity method. Examples are given to demonstrate the effects of off-reef fracturing and the importance of stope-fault intersections during seismic events.

Jan 1, 1991

"Chairman: Dr N. G. W. Cook Rapporteur: Mr M. P. RobertsPapers:Planning open pit mining operations using simulation by A. Bauer and P. N. Calder Simulation for control of underground liquid flow by G. N. Pitts and P. B. CrawfordEvaluation of production strategies in a group of copper mines by linear programming by P. H. Williams, J. N. Brooke and D. M. PoulterAn equipment maintenance system by D. W. Dean and J. A. RyderTaken as a whole, the difference between the four papers in this session were perhaps more illuminating than their similarities. The titles of the first and second papers contained the word 'simulation', and in both papers random number generation was relied upon in the selection of inputs from empirical distributions, but the nature of the models to which these values were inputs were quite different. The third paper displayed another method of uniting the empirical and the theoretical in a linear programming formulation whose matrix coefficients were measured empirically, and here some apt remarks on computer implementation were included. This paved the way for the last paper which abandoned all theoretical pretensions in favour of a detailed description of computer implementation and perhaps as a result gave rise to the most feeling audience participation.The systems mentioned were developed for the iron, petrol, copper and gold producing industries in the US, Canada, Zambia and South Africa..As with all the parallel sessions, contributions from the floor may have been limited by the shorter time available to delegates to acquaint themselves with the papers before the session. In spite of this, and due largely to the active chairman¬ship of Dr Cook, the discussion during the session which is summarized here contributed much to the information contained in the papers themselves.In his presentation, Dr Calder summarized his paper. He expected that simulation would be used in future on an almost universal basis in open pit mining. It could contribute new knowledge more cheaply than experimentation in the flea For example, this study had shown what was previously thought to be a matter of more shovels and trucks was really a blasting problem, and improving blasting had increased production to the desired level. The simulation had shown that uniformity of truck performance was a desirable factor. It had also been used to study the advisability of a dispatching system.Dr Ramani contended that where equipment characteristics were available, deterministic standard simulation could adequately simulate systems in which interference occurred. Operator performance could be measured against perfor¬mance curves predicted by standard simulation and poor operators spotted and retrained. The present system did not take into account variability in truck loading, for instance. Dr Calder replied that if the number of variables was large, the standard approach became too complicated for operating personnel to follow. He admitted he had not tried it. The variability of truck loading could be coped with easily using the Monte Carlo approach. Operator variability was already incorporated because the time studies are actual."

Jan 1, 2014

By K. Forsberg, Ş. Kaya, C. Dittrich, M. Svärd, E. M. Peters

Scandium can be recovered from waste streams of other metallurgical processes such as red mud from the Bayer process and titanium dioxide acid waste. This is accomplished by an integrated process comprising leaching using acidic media, solvent extraction using organic solvents and stripping of Sc from the organic phase using NH4F solutions. The precipitation of scandium as (NH4)3ScF6 from NH4F strip liquors has been demonstrated at lab-scale with recoveries and purities greater than 98% and 98.3%, respectively. It is desired to assess the possibility of recovering the solvents for re-use in the process to improve its economy and environmental friendliness. Investigations have been conducted to recover alcohol by simple distillation from strip liquor-alcohol mixtures containing about 50 v/v% alcohol. The mixtures were obtained after anti-solvent precipitation of (NH4)3ScF6 using an alcohol to strip liquor volumetric ratio of 1:1. The starting strip liquor contained about 2000 mg/L scandium in 3 mol/L NH4F solution. In the recovery of methanol, the first distillate product collected had a purity of about 87 v/v% and this decreased slightly with time over two hours. The methanol distillate collected in the first 30 minutes with a purity of ca. 85 v/v% was re-used in anti-solvent crystallisation of (NH4)3ScF6 from the initial strip liquor, and the scandium recovery attained was about 98.6 w/w%, almost similar to that of 99.2 w/w% obtained using 100 v/v% methanol. For ethanol recovery, the first distillate product collected was approx. 84 v/v% pure and the distillate collected in the first 30 minutes with a purity of about 75 v/v% achieved a scandium recovery of about 97.2 w/w% in comparison to 98.5 w/w% obtained using 100 v/v% ethanol during anti-solvent crystallisation. Keywords: Alcohol recovery, methanol, ethanol, anti-solvent crystallisation, (NH4)3ScF6

Jan 1, 2020

By W. F. McKechnie

"Southern Africa is generally thought to be well explored, with only limited potential for major new diamond discoveries. However, Chiadzwa in Zimbabwe and reports of a significant new kimberlite find in Angola are testimony to the dangers attached to an attitude that ‘there is nothing left to find’.Since the major discoveries in the central interior of South Africa in the 1870s, diamond exploration in the region has been led by market and political factors that influence the key exploration drivers of opportunity and value proposition. Unexpected new discoveries by new players always impact on existing producers and, from time to time, denial of opportunity through political or protectionist policies has inhibited investment in exploration.Entrepreneurial exploration appetite in southern Africa will be tempered by the potential value equation and security of investment. Overlaid on this, developments in diamond recovery technologies provide opportunity to reinvigorate current mines and old prospects previously considered too difficult or costly to exploit. Position on the cost curve will remain a key factor for survival in an increasingly competitive environment. IntroductionThe diamond industry in southern Africa boasts a history of 150 years of discovery and mining, forming the cornerstone of development of the core, modern economies at the southern tip of Africa.Since the discovery, in the 1860s and 1870s, of the secondary diamond placers and primary diamond-bearing kimberlite deposits in the central interior of the then Cape Colony and Orange Free State, southern Africa has endured as the pre-eminent diamondproducing region in the world. Notwithstanding periodic competition from significant new discoveries in other parts of the globe and the paucity of recent, new discoveries in the region, its ranking is unlikely to change in the short to medium term.In a geological context the region contains the Kaapvaal-Zimbabwe and Angola-Kasai cratons, identified in terms of Clifford’s rule as areas inherently prospective for diamonds, being underlain by portions of the Earth’s crust that are tectonically stable and older than 1.5 billion years (Clifford, 1992). Although the Democratic Republic of Congo (DRC) would, in a geographic context, be considered to be part of Central Africa, for the purposes of this review it is included in southern Africa since northeast Angola and the adjacent parts of the DRC form part of the same geological terrane and diamond production from both countries needs to be considered together. Historical and current diamond production from the northeastern parts of the DRC around Kisangani is not considered to be significant and its inclusion in the overall numbers for the DRC does not materially affect the overall picture presented here."

Feb 1, 2019

By G B. Gnoinski

The Skorpion Zinc Mine and Refinery is situated approximately 25 km north of Rosh Pinah, south-western Namibia. The supergene zinc oxide deposit at Skorpion is hosted in a volcano-sedimentary succession within the para-autochthonous Port Nolloth Zone of the Gariep Belt. Rock types hosting the ore deposit include altered and metamorphosed volcaniclastic and clastic sediments, limestone and rhyolite. At Skorpion, the metallurgical process is unique and the plant design requires minimal fluctuations within a selected feed grade. In addition, the presence of limestone inter-fingered with ore in some areas of the deposit results in dilution problems which may increase gangue acid consumption and therefore processing costs. Hence, selective mining is necessary to ensure the delivery of suitable ore to the processing plant, in order to keep the overall operating costs at a minimum. A complex control system is in place and is capable of a high degree of selectivity. The paper describes the grade control system in place at Skorpion Mine which ensures that the qualities of the blocks planned for mining and the material being mined meet the stringent process requirements of the refinery, i.e zinc grade, gangue acid consumption and deleterious elements that may impact on the efficiency and costs of the metallurgical process. Keywords: Skorpion zinc, zinc oxide, supergene, volcano-sedimentary, grade control

Jan 1, 2007

By T. J. Goff

Keywords: accurate control, matte level, smelting operations, process control, tapping, sounding bar, electromagnetic measurement [ ] Accurate control of matte levels during primary matte smelting operations is desirable in order to improve process decision-making. High matte levels in the vessel could have to disastrous consequences, particularly in the new generation of intensive smelting furnace with deep-cooled copper coolers. Knowing when to commence tapping and a better understanding of melt times can only be improved if the furnace levels are monitored correctly. At Lonmin Marikana Smelter Division it has long been understood that the matte level information being provided by the manual sounding bar is only as good as the operators? following of measurement procedure, their skill in assessing what the sounding bar is displaying, and their individual interpretation of what they are looking at. This paper sets out to show how this problem was identified as an area of major concern to the plant, how a solution was sought and how an electromagnetic measurement system was installed as an alternative measurement to the matte sounding bar system. Other areas discussed in the paper are the difficulties to be overcome when first installing new equipment and how these teething problems were solved by close co-operation between Lonmin and equipment suppliers, which led to some design modifications to the delivery system. In conclusion the paper discusses the results between the electromagnetic measurement and the manual sounding measurement and how best to integrate the generated data into the plant?s process control system for improved decision making.

Jan 1, 2011

By G. H. Grange

Details are given of three legal controls for the pollution of the air, the water, and the land, together with brief histories of the developments leading up to these controls. Attention is drawn to the fact that legal action may be instituted against a mine under common or other laws where pollution causes proveable damage or loss. It is suggested that an international conference should be held to define the philosophies and principles on which to base not only the necessary legislation for environmental control but also the machinery by which the controls can be administered.

Jan 1, 1978

By D. N. Ferguson

The separation of certain minerals by electrostatic techniques can be difficult due to their similar electrical conductivity, and any technique to improve this can be useful in certain difficult separation applications. Triboelectric differences between mineral scan result in certain minerals acquiring small positive or negative charges prior to inductive electrostatic separation. By changing the polarity of inductive separation, relative changes in mineral recovery can be observed, which may be beneficial. In this brief study a JKTech mineral liberation analyser (MLA) was used to evaluate the effect of polarity change on selected minerals present in the Richards Bay Minerals deposit, and an approximate triboelectric series based on this behaviour is presented.

Jan 1, 2010

By M. H. Dehghanpoor, M. Zivdar, M. Torabi

"A hydrometallurgical route was developed to extract metals such as gold, silver, copper, and selenium from anode slime from Sarcheshmeh Copper Complex in Iran. For the extraction of copper by leaching, the anode slime was heated and stirred with 4 M sulphuric acid in the presence of oxygen. Optimal conditions for recovery of copper were temperature 80°C, mixing time 5 hours, and oxygen flow rate 2 L/min, resulting in a copper recovery of 94.47%. Silver and selenium were dissolved by leaching anode slime from which the copper had been removed with nitric acid. For gold extraction, anode slime was heated with aqua regia at 90°, and the gold then extracted with 2-ethyl-hexanol at a concentration of 0.5 M and phase ratio of 4. The extract was then stripped with soda solution at pH=10.5 and a phase ratio of 5. Finally, gold was recovered by precipitation with oxalic acid at a ratio of mass to volume 10 g/L. Total gold recovery was 80%. IntroductionDuring the electrorefining of copper, some metals are accumulated in the byproduct anode slime, which is an important source for recycling and recovery of these metals (Petkova, 1994). In this paper, a hydrometallurgical route is described for the recovery of precious metals from copper anode slime of Sarcheshmeh Copper Complex, which is located in southeastern Iran .Copper anode slime is black or gray powder with a particle size less than 200 mesh. Approximately 2 to 20 kg of anode slime is produced per ton of copper cathode. The slime is characterized by higher amount of Ag, Se, Pb, and Cu compared to other metals and a very low Au content (Khaleghi and Ghader, 2013).The copper anode slimes are composed of 11.69% selenium, 3.93% copper, 5.26% silver, 0.13% gold, and 45% barite, plus lead, tellurium, antimony, sulphur, and silica with small amounts of nickel, iron, zinc, and bismuth. Gold is one of the most important noble metals due to its wide applications in industry and economic importance, so recovery of gold from slime is more appealing than that of other metals. According to the World Gold Council (2013), the demand for gold has increased during the last decade. This increase is due not only to the increasing demands of the jewellery market, but also to the increasing demand for gold in industrial as well as medical applications (Ranjbar et al., 2014)."

Jan 1, 2016

By S. M. Spottiswoode

Much as one hopes to predict whether damaging seismicity might occur somewhere in the next shift, this is not possible at present. Recently, an analysis of seismicity at two mines has shown that a small increase in seismicity occasionally occurs before both large and small events. This analysis is extended here to five mines, with the same results. Earthquake seismologists forecast hazard in terms of the average incidence of earthquakes over the last 50 years, adjusted on an hourly basis according to the possibility of aftershocks of events that have happened. The rate of seismicity in any area remains approximately constant when expressed as seismicity per area mined, or better still, per unit of elastic strain energy released. It is suggested that seismic hazard in mines be estimated using historical seismicity and forward modelling, adjusted according to the possibility of aftershocks. In summary, medium-term forecasting of seismicity is viable; short-term prediction of large events is not.

Jan 1, 2010

By P. K. Hofmeyr

Base Metal (Cu, Ni, Mo, Zn, Co etc.) analysis traditionally has been very slow in conventional analytical laboratories which can lead to additional costs being incurred in waiting time of drill rigs or mining excessively off-reef. Recent developments in the automation of analytical laboratories now allow for very rapid turn-around times for base metal analytical data which can help reduce such costs as well as reduce the unit costs of the analyses themselves. 2.0 CONVENTIONAL ANALYTICAL LABORATORY PRACTICE Conventional analytical laboratories are necessarily are very manual. Sample preparation is slow and laborious, samples are moved from stage to stage manually and, typically, all samples are processed in batches so a sample which is the first to be, say, milled has to wait for the complete milling of the batch before it advances to the next stage eg. mixed with wax prior to pelletising for XRF analysis. Inevitably this results in long sample data turn-around times for laboratories handling large numbers of samples. Manual sample preparation can only be accelerated by increasing staff which increases costs and can lead to additional errors being introduced. Cleaning of sample preparation equipment, eg. crushers and mills, between samples is essential to avoid cross-contamination between samples and this is slow and labour-intensive. In manual sample preparation the correct sample numbers staying with the samples is totally dependent on the efficiency of laboratory operators. It is extremely difficult to detect when errors have occurred due to the switching of sample numbers during the sample preparation stages. Running duplicates and QC samples at best is only partially successful in detecting when sample number switching errors have occurred. Errors of this nature and cross-contamination problems due to incomplete cleaning of sample preparation equipment tend to occur when laboratories are working at pressure due to high sample numbers and when supervisors are not present during 24/7 laboratory operations which is often required on plant process control laboratories. These problems are common to all conventional analytical laboratories and their magnitude is dependent on the level of control and efficiency of QC systems practised by individual laboratories. The disadvantages of conventional manual analytical laboratories can be summarized as follows:- 1. Labour-intensive which is costly especially when multiple shifts have to be used during 24/7 operations.

Jan 1, 2005

Four engineering products and three consumer products have received awards in the 1978 Shell Design Awards competition organized by the Design Institute of the South African Bureau of Standards. Norman Hanson Visiting Fellowship The Norman Hanson Visiting Fellowship, supported jointly by the National Development Fund for the Building Industry (inaugurated by the Building Industries Federation (8.A.)), the Institute of S.A. Architects, the Association of S.A. Quantity Surveyors, and the National Building Research Institute of the CSIR exists to finance fully or wholly visits by eminent authorities from overseas to South Africa for the purposes of seminars, informed discussions, consultation, and possible active participation in scientific, technological, and development projects of importance to the building industry.

Jan 1, 1979

The rising tide of environmentalism has adversely affected many mineral producers, but it has also provided them with a number of opportunities for mineral applications. These markets are as diverse as water treatment, waste disposal, and flue-gas desulphurization. Whilst legislation is forcing up the industry's environmental standards, the advent of environmental management provides an opportunity for producers to display its 'green' credentials. The picture painted of the extractive industry by environmentalists is undeservedly black, because the more efficient a producer is, the more effectively that producer conserves the very resources he exploits. The 1993 IM Forum examined these issues and how they affect the mineral producer, and this publication comprises the papers presented at that meeting.

Jan 1, 1995

By Gaspard Devos

1. A NEW CONTEXT FOR METAL INDUSTRY Producers and owners of industrial extractive sites are living hard times due to Environmental pressure and liabilities. This is valid whatever the region in the world, it is just a question of time. On one hand, the normative environmental pressure is increasing through more severe regulations and controls on all pollution sources and production materials. [ ] Furthermore, more impurities are extracted and captured, more the volume of the related wastes is increasing. But disposal costs are increasing, disposal areas for wastes are restricted, markets for wastes are limited and technologies for waste treatment are, most of the time, not available. On the other hand, for most of the extractive industries, the costs required to get access to refine primary raw material are killing the profitability of the industry. Definitively, a technological and economical breakthrough is ongoing: extractive industries have to increase their feed from secondary material and to be involved more and more with the recycling business.

Jan 1, 2005

By G-L. Wu, X-B. Liu, C-Y. Zhou

"The static recrystallization behaviour of Ti-Nb microalloyed high-strength steel during hot deformation was studied by conducting double-hit hot compression experiments using a Gleeble-3500 thermomechanical simulator. The effects of deformation temperature, strain rate, strain, and initial austenite grain size on the static recrystallization fraction are discussed. The static recrystallization kinetics were modelled, and the results show that the static recrystallization fraction increased with deformation temperature, strain rate, and strain and interpass time. The static recrystallization activation energy Qs was 326.05 kJ mol-1. Comparison of the experimental results and predicted results indicates that the effects of deformation parameters on the static recrystallization in multistage hot deformation are significant. The predicted results are in good agreement with the experimental results. IntroductionIn hot-forming processes, complex microstructures are often induced by multiple hot deformation mechanisms (Zhang et al., 2014; Liang et al., 2015). The softening behaviour during hot processing has generated considerable interest because component properties are influenced significantly by the corresponding microstructural evolution (Wu et al., 2010). It is well known that dynamic recrystallization (DRX); metadynamic recrystallization (MDRX), which occurs by the growth of DRX nuclei during intervals of deformation; and static recrystallization (SRX), which occurs by nucleation and growth during the intervals of deformation, can significantly alter the austenite grain size (Chen et al., 2015. Chen, Sui, and Cui, 2014; Mao et al., 2014). The long interpass times allow complete SRX to take place if the steel is being rolled above the interpass recrystallization stop temperature (Tnr), i.e. in the absence of carbonitride precipitation (Siciliano, 2000). In recent research, microalloying technology coupled with new-generation thermomechanical control processing (NG-TMCP) has proved efficient in achieving the proper balance between strength, toughness, ductility, and formability by means of a suitable combination of chemical composition and thermomechanical treatment parameters (Shukla et al., 2012; Bandyopadhyay et al., 2011). The alloying elements Nb, V, Ti are widely used in high-strength low-alloy (HSLA) steel to achieve the desired strength and toughness properties with solid-solution strengthening, precipitation hardening, grain refinement, and dislocation strengthening (Opiela, 2014; Chen and Yu, 2012). The wide applicability of alloying elements in HSLA steel is due to the fact that heat treatments are not required after forming of the parts, which results in time and cost savings."

Jan 1, 2017