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Snowflakes and Fissures. Chemical and Metallurgical Engineering, Vol. 21 (1919), pp. 216-271-342-478-556. A series of articles and reviews by H. M. Howe, Henry S. Rawdon, C. Y. Clayton, F. B. Foley, F. B. Laney, F. Giolitti, H. Styri, and B. E. Field. Snowflakes, the term commonly applied to the internal ruptures in gun and other forgings, are described in great detail and their origin attributed to a great variety of improper mill practices. In Vol. 22 (1919), p. 145, Mr. E. E. Thum reviews the matter and suggests that oxide films may be the joint origin of flakes in forgings and fissures in rails.

Relationship between Transverse Rail Fissures, Flakes and Defects in Fusion Welds. By S. W. Miller. Chemical and Metallurgical Engineering, Vol. 22 (1919), p. 729. Mr. Miller develops the theory that all three are the result of improper metallurgical practice in allowing films of oxide or nitride, probably microscopic, to persist in the product.

Limiting of Transverse Fissures. By Paul Kreuzpointer. Iron Age, August 7, 1919, Vol. 104, p. 360. A plea for better general mill practice, concluding that transverse fissures are the result of combinations of contributory causes, all capable of control by intelligent effort.

A Metallographic Investigation of Transverse Fissure Rails with Special Reference to High Phosphorous Streaks. By G. F. Comstock. Transactions of the American Institute of Mining and Metallurgical Engineers, Vol. 62 (1919), p. 703. An investigation of 24 transverse fissure rails and 12 good service rails as to the presence of phosphorous streaks in the zone of fissures. In many instances the nucleus of a fissure seems to be located in a phosphorous streak, and practically all the fissured rails examined contained these streaks. It is also suggested that phosphorus is better diffused in reheated blooms than in the direct rolled product. Discussed by Dr. Dudley, C. B. Bronson, G. M. Davidson, James E. Howard, and M. H. Wickhorst. Dr. Dudley presents some information as to the better behavior of reheated blooms. Mr. Wickhorst shows typical transverse fissures and deep etchings, and suggests similarity of origin between flakes in forgings and fissures in rails. Mr. Comstock's paper is abstracted in Railway Age, November 29, 1918. Both the paper and discussion are reviewed from reprints in Engineering News-Record, March 13, 1919, Vol. 82, p. 532. Dr. Dudley's discussion is abstracted in Engineering and Contracting, May 21, 1919, Vol. 51, p. 540.

Microstructural Features of Flaky Steel. By Henry S. Rawdon. Transactions of the American Institute of Mining and Metallurgical Engineers, Vol. 62 (1919), p. 246. Mr. Rawdon states that flakes originate as intercrystalline shrinkage cracks in the ingot and persist into the finished product as discontinuities, often associated with slag films. He also believes that the rate and distribution of cooling stresses have an important role in governing the defects.

Flaky and Woody Fractures in Nickel Steel Gun Forgings. By C. Y. Clayton, F. B. Folev, and F. B. Laney. Transactions of the American Institute of Mining and Metallurgical Engineers, Vol. 62 (1919), p. 211. The authors attribute flakes to overheating and nonuniformity of heat of the ingot, resulting in the incipient fusion of minute grains of highly segregated structure; the working of the metal flattens these grains into films. Thorough soaking through the critical range appears to effect decided improvement in physical properties, and reheating through this range resulted in effacing flakes from material very bad in this respect. These results appear significant in connection with the greater freedom from fissure in rails from reheated blooms and tend to emphasize Mr. Comstock's suggestions regarding the practicability of promoting diffusion of impurities through proper heating. In

comparison with the deep etching of rail heads, the following is of interest. "In etching flaky steel for macroscopic examination it was noted that the flaky areas were attacked more readily than the normal steel and if the sample were permitted to remain long enough in the acid the flake area was eaten out and resembled a minute crack." This also seems suggestive. "That the damage which causes flakes is done after the ingot is poured is indicated strongly by an experiment in which two ingots were cast from the bottom through a common runner; one ingot made a flaky forging and there was no trouble from this source in the other." This article together with the work of Mr. Rawdon are discussed in the same volume of the Proceedings, p. 263, by Messrs. P. E. McKinney, J. A. Mathews, O. A. Knight, F. N. Speller, J. E. Johnson, A. A. Stevenson, J. S. Unger, H. Traphagen, and H. C. Boynton.

1920.

On the Shattered Zones in Certain Steel Rails with Notes on the Interior Origin of Transverse Fissures. By James E. Howard. Proceedings of the American Society for Testing Materials, Vol. 20, Part 2 (1920), p. 44. Mr. Howard presents a review of the work so far accomplished on shattered zones, but seems hardly prepared to consider this condition the basic cause of fissures. The paper is discussed by Messrs. Comstock, Rawdon, Job, and Wickhorst, all of whom seem quite satisfied that the fissure nuclei are identical with "shattering cracks." Abstracts and reviews of the paper and discussion are presented in the following. Iron Trade Review, July 1. 1920, Vol. 67, p. 22. Engineering News-Record, July 8, 1920, Vol. 85, p. 51. Iron Age, July 1, 1920, Vol. 106, p. 20. Chemical and Metallurgical Engineering, June 30, 1920, Vol. 22, p. 1189.

Some Deep Etching Experiments on Steel Rails. By G. F. Comtsock. Chemical and Metallurgical Engineering, December 1, 1920, Vol. 23. p. 108. A large number of samples of new rail accumulated in Mr. Comstock's laboratory for other purposes were deep etched to develop interior shattering if present. No shattered structure was found, but as Mr. Comstock states, the percentage of fissured rail is so small that absence of shattering in a much greater number of new rails would not be evidence against the theory.

Interstate Commerce Commission Report of Chief of Bureau of Safety for Year ending June 30, 1919. Mr. Borland seems to have some confidence in the connection between shattered zones and fissures, as well as the origin of the shattering in thermal conditions at the mill. Abstracted in Railway Age, February 13, 1920, Vol. 68, p. 500.

The Nature of the Defects Revealed by the Deep Etching of Transverse Fissure Rails. By Henry S. Rawdon. Proceedings American Railway Engineering Association, Vol. 21, p. 1219. Mr. Rawdon's work shows that the shattered structure cannot be caused by the etching solution, which some investigators had indicated as possible. By depositing finely divided iron particles out of suspension in kerosene on unetched rail sections previously magnetized, the crack locations appeared as lined by the orientation of the particles. After marking with a punch and removing the particles. etching developed typical cracks in every location. It was also possible to spread the crack sufficiently with a punch to render it visible under a miscroscope without etching. Fracturing through the crack as opened showed a break apparently exactly similar to a fissure nucleus.

Metallographic Features Revealed by the Deep Etching of Steel. By Henry S. Rawdon. Bureau of Standards Technologic Papers No. 156, issued March 19, 1920. This paper includes Mr. Rawdon's work as above on rails and extends the field over gun tubes, ball bearings, cast

steel and wrought iron. Both the papers are reviewed and abstracted in Engineering News-Record, January 15, 1920, Vol. 84, p. 129, and Chemical and Metallurgical Engineering, March 17, 1920, Vol. 22, p. 505.

Interstate Commerce Commission Investigation of Chesapeake and Ohio Accident near Hardware, Va. Report by Chief of Bureau of Safety dated February 21, 1920, of accident on January 7, 1919. Report by Mr. Howard is embodied in which shattered zones are discussed in general connection with fissure failures. This report is abstracted in Railway Age, May 21, 1920, Vol. 68, p. 1466.

Transverse Fissure Rails on Atchison, Topeka and Santa Fe Railroad, Heat 41177. By M. H. Wickhorst. Proceedings of the American Railway Engineering Association, Vol. 21 (1920), p. 1079. Result of drop. tensile and etching tests and chemical analyses on a heat of rail removed from service on account of failure of one rail from transverse fissure. The drop tests revealed a number of growing fissures and some gray spots. The rails showing fissures and to some extent the rails with gray spots exhibited shattered structure on deep etching, while the rails from the balance of the heat were free from shattering.

Are the Nuclei of Fissures Cracks? By M. H. Wickhorst. Proceedings of the American Railway Engineering Association, Vol. 21 (1920), p. 1183. Pieces from fissured rails were heated to 1400 F. and quenched in water. If grain continuity extends through the fissure nucleus or gray spot, then the grain should be refined to a noticeable extent by this treatment. However, on breaking the pieces a total of three fissures and one gray spot were exhibited, and the grain of all appeared identical with the usual structure. This is good evidence of discontinuity of structure, or crack, in the rail.

Examination of Rails Long in Service for Relation Between Internal Stresses and Strains and Transverse Fissures. By W. C Cushing. Proceedings of the American Railway Engineering Association, Vol. 21 (1920), p. 1189. A large number of rails ranging from 10 and 45 years in service were examined under the drop to disclose transverse fissures and none were found. Internal stresses of considerable magnitude were shown to exist and the thought is strongly developed that service in track cannot develop fissures unless it has defective metal to work upon.

What is Brittleness in Steel Rails? By M. H. Wickhorst. Proceedings of the American Railway Engineering Association, Vol. 21 (1920), p. 1229. Various classes of brittleness are analyzed and great stress is laid upon the necessity of drop testing with the head down, that is in tension, so as to prove the duitility in the zone of fissures.

Review of Work on Transverse Fissures. By Dr. P. H. Dudley. Proceedings of the American Railway Engineering Association, Vol. 21 (1920), p. 1240. Reviews the work of Cushing. Waring, and Wickhorst and states that his own laboratory is proceeding with extensive tests of the usefulness of the magnetic survey as a test on new rails for soundness. The conductivity of metal to magnetic flux appears to bear some relation to the interior structure in degrees capable of registration as a considerable variation at different points on a rail bar. The interpretation of the result is not as yet clear.

The Relation of Shattered Steel in Fissured Rails to the Mill End of the Rail. By M. H. Wickhorst. Rail Report No. 90. American Railway Engineering Association Rail Committee. July, 1920. Will appear in Proceedings, Vol. 22 (1921). Shows that shattering cracks do not extend nearer than one-half inch to the hot sawed end of the rail. This is a strong indication that the crack develops on the hot bed as a shrinkage crack.

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The following subjects were assigned to the Committee on Economics

of Railway Labor and report thereon is submitted herewith:

1. Report on plans and methods for obtaining railway labor.

2. Study and report on methods for training and educating employees in engineering and maintenance work.

3. Study and report on standard methods for performing maintenance of way work for the purpose of establishing units of measure of work performed.

The subjects assigned are identical with those your Committee had under consideration during 1920; progress having been reported at the last convention on items one (1) and two (2).

The work of your Committee the past year has, to a large extent, embraced a study of the data assembled during 1920, and the coördination of certain well-defined principles and practices in order to formulate conclusions that may be helpful to the railways in solving their individual as well as general labor problems.

ACTION RECOMMENDED

1. The Committee recommends that the conclusions in Appendices A, B and C be approved and published in the Manual.

Respectfully submitted,

THE COMMITTEE ON ECONOMICS

OF RAILWAY LABOR,
C. E. JOHNSTON, Chairman.

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