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By Ulrich H. Roesler

RECENTLY, C. Zener1 published a new thermo-dynamic treatment of the a/y transformation in iron alloys. His interpretation differs from the previous theories2-0 ainly through the separation of the free energy difference, Ga—G, into two additive

Jan 1, 1957

By Walter R. Hibbard

BACKOFEN' reported recently that "the deformation texture of cold-drawn OFHC copper wire, after a reduction in area of 97.3 pct, may still be described as a composite of [lll.] and [loo] directions aligned parallel to the wire axis." In the introduction, he indicated that this was in contrast to the work of Hibbard,' who reported a single [111] texture after a reduction of 96.4 pct. Unfortunately Backofen stated that this was a reduction in area when actually it was a reduction in diameter, as is clearly stated in the reference. Moreover, the results of Backofen are in complete agreement with the results of Hibbard. Backofen's 97.3 pct reduction in area is an 83.3 pct reduction in diameter, after which he foundadouble [ll11 and[l001texture with the former predominating. Similarly, Hibbard; after an 86 pct reduction in diameter found a double [Ill] and [I001 texture with the former predom- inating. Hibbard, however, when he drew the wire further to 96.4 pct reduction in diameter, found primarily a single [Ill1 texture as illustrated by Fig. 2 of ref. 3. Here also, Hibbard- reported evidences of the [loo] recrystallization texture found by Backofen. It might also be pointed out that Backofen not only drew his wire 97.3 pct reduction in area but also etched them over 99 pct reduction in area from 0.125 to 0.01 in. diam. Hibbard's wires were drawn directly to size. In summary, the deformation texture of cold-drawn copper wire still may be described as primarily a single Clll] texture after a sufficient amount of drawing, such as 96.4 pct reduction in diameter." a

Jan 1, 1952

By R. A. Jr. Flinn

A CONSIDERABLE number of experiments in recent years have definitely established the fact that the internal friction or mechanical hysteresis of a metal under cyclic stress is a property that is highly "structure sensitive." Because of this fact, it has been suggested that an observa-tion of this property, which often is referred to as "clamping capacity," might he a useful indicator of structural changes taking place when a metal or alloy is subjected to any of a number of metallurgical treatments. Damping capacity is of interest to both engineer and metallurgist, but from a rather different point of view, and the information that each desires from such observations is of a different nature. The metallurgist is in search of various external indications of changes taking place in the interior of a metal; changes which are in themselves not directly observa-ble. Even if the observed phenomenon cannot be explained in funda-mental terms, it may be empirically related to certain characteristics of the material and prove of real value in research. Internal friction or mechanical hysteresis occupies such a position, and, although it is not well understood in terms of basic metallic theory, an observation of its changes can serve in a very useful capacity. Of course, there is nothing new in the measurement of damping, but the use of this property in metallurgical research constitutes a vast field, which has received all too little attention. The present work is essentially of an exploratory nature in this field and is an attempt to evaluate the process as a research tool. The phenomenon of age-hardening was chosen as a typical example of a structural change and one method of measuring damping was examined in considerable detail.

Jan 1, 1938

By R. A. Flinn, John T. Norton

A CONSIDERABLE number of experiments in recent years have definitely established the fact that the internal friction or mechanical hysteresis of a metal under cyclic stress is a property that is highly "structure sensitive." Because of this fact, it has been suggested that an observation of this property, which often is referred to as "damping. capacity," might be a useful indicator of structural. changes taking place when a metal or alloy is subjected to any of a number of metallurgical treatments. Damping capacity is of interest to both engineer and metallurgist, but from a rather different point of view, and the information that each desires from such observations is of a different nature. The metallurgist is in search of various external indications of changes taking place in the interior of a metal; changes which are in themselves not directly observable. Even if the observed phenomenon cannot be explained in fundamental terms, it may be empirically related to certain characteristics of the material and prove of real value in research. Internal friction os mechanical hysteresis occupies such a position, and, although it is nor well understood in terms of basic metallic theory, an observation of itt changes can serve in a very useful capacity. Of course, there is nothing new in the measurement of damping, but the use of this property in metallurgical research constitutes a vast field, which has received all too little attention: The present work is essentially of an exploratory nature in this field and is an attempt to evaluate the process as a research tool. The phenomenon of age-hardening was chosen as a typical example of a structural change and one method of measuring damping was examined in considerable detail.

Jan 1, 1938

By R. A. Flinn, John T. Norton

A considerable number of experiments in recent years have definitely established the fact that the internal friction or mechanical hysteresis of a metal under cyclic stress is a property that is highly "structure sensitive." Because of this fact, it has been suggested that an observation of this property, which often is referred to as "damping capacity,'' might be a useful indicator of structural changes taking place when a metal or alloy is subjected to any of a number of metallurgical treatments. Damping capacity is of interest to both engineer and metallurgist, but from a rather different point of view, and the information that each desires from such observations is of a different nature. The metallurgist is in search of various external indications of changes taking place in the interior of a metal; changes which are in themselves not directly observable. Even if the observed phenomenon cannot be explained in fundamental terms, it may be empirically related to certain characteristics of the material and prove of real value in research. Internal friction or mechanical hysteresis occupies such a position, and, although it is not well understood in terms of basic metallic theory, an observation of its changes can serve in a very useful capacity. Of course, there is nothing new in the measurement of damping, but the use of this property in metallurgical research constitutes a vast field, which has received all too little attention. The present work is essentially of an exploratory nature in this field and is an attempt to evaluate the process as a research tool. The phenomenon of age-hardening was chosen as a typical example of a structural change and one method of measuring damping was examined in considerable detail. Methods of Measuring Damping Capacity Many kinds of observations can be made upon a specimen subjected to a cyclic stress from which can be calculated the energy absorbed in

Jan 1, 1938

By R. A. Flinn, John T. Norton

A considerable number of experiments in recent years have definitely established the fact that the internal friction or mechanical hysteresis of a metal under cyclic stress is a property that is highly "structure sensitive." Because of this fact, it has been suggested that an observation of this property, which often is referred to as "damping capacity,'' might be a useful indicator of structural changes taking place when a metal or alloy is subjected to any of a number of metallurgical treatments. Damping capacity is of interest to both engineer and metallurgist, but from a rather different point of view, and the information that each desires from such observations is of a different nature. The metallurgist is in search of various external indications of changes taking place in the interior of a metal; changes which are in themselves not directly observable. Even if the observed phenomenon cannot be explained in fundamental terms, it may be empirically related to certain characteristics of the material and prove of real value in research. Internal friction or mechanical hysteresis occupies such a position, and, although it is not well understood in terms of basic metallic theory, an observation of its changes can serve in a very useful capacity. Of course, there is nothing new in the measurement of damping, but the use of this property in metallurgical research constitutes a vast field, which has received all too little attention. The present work is essentially of an exploratory nature in this field and is an attempt to evaluate the process as a research tool. The phenomenon of age-hardening was chosen as a typical example of a structural change and one method of measuring damping was examined in considerable detail. Methods of Measuring Damping Capacity Many kinds of observations can be made upon a specimen subjected to a cyclic stress from which can be calculated the energy absorbed in

Jan 1, 1938

By Stanley C. Suboleski, J. Richard Lucas

Simulator I, a program to simulate production in room and pillar mining systems containing up to six face operations, was developed at Virginia Polytechnic Institute under sponsorship of the Office of Coal Research. Since its inception, several hundred analyses have been run, with over thirty companies using the program. This paper describes the simulation technique used in this program, the output achieved from an analysis, and reviews the experience gained in working with Simulator I.

Jan 1, 1969

By Robert Spring

The kinetic ball mill model accurately simulated two industrial mills over their entire operating range. This was confirmed using 100 sets of grinding circuit data. Contrary to initial expectations, the absolute grinding rate function was not correlated to the mill feedrate, feed size distribution or pulp density. Instead, a single rate function provided excellent simulation over the entire operating range. Statistical analysis showed that the model explained all significant variation in measured product size distributions.

Jan 1, 1984

By James A. Burns

The challenge to designers of bulk materials handling systems is to apply the existing technology in areas where it has not been used and to foster better, cheaper and safer job performance. The Dashaveyor Co., a subsidiary of The Bendix Corp., built and tested a pilot system at Copper Range's White Pine mine. Based upon this success, a prototype system development was begun in 1967 to test the concepts in a full-scale, realistic environment.

Jan 11, 1973

By Shiou-Chuan Sun, R. F. Wesner, J. D. Morgan

A new apparatus termed a "distribution analyzer" is introduced to ascertain the optimum conditions of electrostatic separation of minerals. It was found that with similar surface condition, testing environment and a constant feed rate of not higher than one layer of particles fed on the grounded roll of the separator, the behavior of each component mineral in a synthetic mixture or ore is roughly similar to that of the same mineral when tested alone.

Jan 3, 1950

By Edwin B. Douglas

The Blackbird mine is owned by Calera Mining Co., subsidiary of Howe Sound Co. The mine is located in the Salmon National Forest, Lemhi County, Idaho, about 22 miles west of Salmon and 220 miles north of Pocatello. The thought of producing cobalt from a prospect that offered excellent opportunities stimulated everyone connected with this project. But as time went on, it was found that every phase of the development presented unusual difficulties.

Mar 1, 1956

A method has been developed to remove calcite from the leaching circuit in the uranium in situ leaching system. The process involves injecting the leachate and a pH control agent tangentially into an inverted cone reactor containing calcite seed catalyst. The leachate can be treated at high throughput to obtain clear effluent containing 5 ppm or lower Ca. Both lime and ammonia are effective pH control agents and consumed according to stoichiometry.

Jan 1, 1985

The following list contains the names of members of whose deaths notices have be received at the Secretary's office between Jan. 1, 1935, and April 1, 1936. Bio¬graphical sketches published in MINING AND METALLURGY are indicated in the last two columns.

Jan 1, 1936

By Richard M. Foose

The year 1950 has been a fascinating and unusual one as far as industrial minerals are concerned because of the sudden development of a critical international situation in late June. The first half of the year was marked by thriving peacetime conditions.

Jan 2, 1951

By M. Adnan Goksel

The paper describes the most common cold bond processes including the Carbonate-Bond, Grangcold, Cobo, MTU and others, and outlines these along with bonding mechanisms, physical and chemical characteristics of the products, and applications to various minerals and waste materia1s.

Jan 1, 1977

By Michel T. Halbouty

South Texas, one of the world's important oil and gas-producing areas, continued to hold interest during 1939 as another scries of new fields and new producing levels was developed within its boundaries at a fairly continuous rate throughout the year. There were 1801 wells drilled in this area in 1939, compared to 1678 in 1938; of these, 1515 were drilled in established fields, or as extensions to proven areas (semi-wildcat), and 286 were drilled as rank wildcats, in search of new production. Among these rank wildcats, 22 produced oil, 7 produced distillate and gas and 257 were abandoned as dry holes (see Table 5). Of the 1515 field and cxtension wells, 1213 produced oil, or distillate and gas, 50 produced only gas and 252 were dry; 38 found new productive sand levels in proven ficlds. Jim Wells County led this district in discoveries, having had 9 new fields arid 9 new productive sands found within its border during 1939. Most activc of the 1939 discoveries were Reynold?; and Ben Bolt fields in Jim Wells County and Minnie Bock field in Nueccs County; among producing fields the most activc were: East White Point and Aransas Pass (McCampbell). Production from South Texas in 1939 totaled 55,105,506 bbl. against a total of 56,152,122 bbl. produced in 1938. South Texas should continue its present rate of developrnent and exploration and this should result in the discovery of many fields in its numerous oil-bearing zones, and should also lead to more knowledge of the possibilities of its deeper horizons, such as the Mt. Selman and Wilcox formations; with the latter holding particular interest at the present time. Tide Water Associated Oil Company's A. M. Bruni No. I, Cole-Bruni field, Webb County, the deepest well drilled along the Mirando trend, was carried to 8959 ft., where it started to blow out from a Wilcox sand topped at 8954 ft., making gas, distillate and mud under heavy pressure. After the well was killed, drill stem beeame stuck and was cemented in place in order to test a Queen City (Mt. Selman) sand logged from 5620 to 5675 ft. This and other shows found in other wells along this trend, but out of this district, have served to increase the importance of this but little explored Sparta-Wilcox trend of South Texas during the year, and more activity along it is to be expected in the near future.

Jan 1, 1940

By Michel T. Halbouty

South Texas, one of the world's important oil and gas-producing areas, continued to hold interest during 1939 as another scries of new fields and new producing levels was developed within its boundaries at a fairly continuous rate throughout the year. There were 1801 wells drilled in this area in 1939, compared to 1678 in 1938; of these, 1515 were drilled in established fields, or as extensions to proven areas (semi-wildcat), and 286 were drilled as rank wildcats, in search of new production. Among these rank wildcats, 22 produced oil, 7 produced distillate and gas and 257 were abandoned as dry holes (see Table 5). Of the 1515 field and cxtension wells, 1213 produced oil, or distillate and gas, 50 produced only gas and 252 were dry; 38 found new productive sand levels in proven ficlds. Jim Wells County led this district in discoveries, having had 9 new fields arid 9 new productive sands found within its border during 1939. Most activc of the 1939 discoveries were Reynold?; and Ben Bolt fields in Jim Wells County and Minnie Bock field in Nueccs County; among producing fields the most activc were: East White Point and Aransas Pass (McCampbell). Production from South Texas in 1939 totaled 55,105,506 bbl. against a total of 56,152,122 bbl. produced in 1938. South Texas should continue its present rate of developrnent and exploration and this should result in the discovery of many fields in its numerous oil-bearing zones, and should also lead to more knowledge of the possibilities of its deeper horizons, such as the Mt. Selman and Wilcox formations; with the latter holding particular interest at the present time. Tide Water Associated Oil Company's A. M. Bruni No. I, Cole-Bruni field, Webb County, the deepest well drilled along the Mirando trend, was carried to 8959 ft., where it started to blow out from a Wilcox sand topped at 8954 ft., making gas, distillate and mud under heavy pressure. After the well was killed, drill stem beeame stuck and was cemented in place in order to test a Queen City (Mt. Selman) sand logged from 5620 to 5675 ft. This and other shows found in other wells along this trend, but out of this district, have served to increase the importance of this but little explored Sparta-Wilcox trend of South Texas during the year, and more activity along it is to be expected in the near future.

Jan 1, 1940

PAGE Problems of American Railroads Early in 1936, by J. J. Pelley 3 The Heavier Nonferrous Metals in Transportation, by C. H. Mathewson... 9 Light-weight Metals in the Transportation Industry, by Zay Jeffries 21 Trends in the Metallurgy of Low-alloy, High-yield-strength Structural Steels, by H. W. Gillett 40 Structural Steels and Light-weight Metals in the Transportation Industry, by Horace C. Knerr 62 Proposed Use of Alloys in Merchant Shipbuilding, by Edgar P. Trask 66 Mutual Effects of Metallurgy and Speed in the Automotive Industry, by Merrill C. Horine 84 The Railroads and Light-weight Equipment, by W. W. Colpitts 93

Jan 1, 1936

By Alan B. Nicol, W. T. Parry

The outcome of these tests has been twofold. They have served to demonstrate that the tiltmeter is a useful and dependable instrument which could prove to be of significant value in reaching the goals of landslide prediction and control, and they have raised a good many more questions about the mechanism of slides than they have answered. It seems likely that many of the old concepts and assumptions will be modified or discarded as more knowledge of actual field phenomenon is gained. Safety and economy are paramount concerns in determining slope stability. These two considerations govern the feasibility and character of slope construction from start to finish.

Jan 1, 1970

Louis S. Cates was born in Boston, Massachusetts, on December 20, 1881. When Cates was in his teens, the family lived at Chestnut Hill, Mass., and he went to the public high school. Then he entered M.I.T., at first in the Department of Electrical Engineering. Next door to the Cates family lived a Mr. & Mrs. Armstrong, who were especially fond of Louis Cates. The latter always called Mr. Armstrong "Uncle." Mr. Armstrong was connected with Kidder Peabody investment firm in Boston. That firm had an office in London and Mr. Armstrong persuaded Cates, before he graduated from M.I.T., to go to work in the London office.

Jan 3, 1964