The mechanical properties of iron & steel are effected by temperature. Mechanical tests were made at high temperature range, from 20°C to 1, 000°C.
The contents of this paper are as follows.
1. History 2. Impact bending test at high temperature 3. Impact tensile test at high temperature 4. Ordinal tensile test at high temperature 5. Repeated bending test at high temperature 6, Summary.
Materials used are; -6 plain carbon steels of various carbon content, from 0.1% to 1.2%; nickel steel; nickel-chrome steels; Ni-Cr-molybdenum steel; stainless steels for turbine blade; alloy steels for valve of aero-engine.
Impact bending test was operated on the apparatus specially constructed to fit on the Izod impact testing machine & special device was applied to impact the specimen just at the temperature wanted. The relationship between carbon content, temperature & impact figure was determined.
Impact tensile test at high temperature was made on another new apparatus and the results were compared with those of slow tensile test and impact bending test.
Special testing machine for repeated bending at high temperature was also constructed and some research was made with various carbon steels.
The comparison of each mechanical properties is described and the theoretical interpretation is given.

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(a) The writer coated the various mixtures of graphite and carborundum on wrought iron bars and deposited a series of cast iron, from grey to white, by using the coated bars as electrodes.
(b) He conducted chemical analyses, hardness tests and microscopic examinations of the deposits and selected three kinds of electrodes suitable for grey cast iron welding.
(c) He determined the optimum quantities of the coating towards the bars, tested what effect we could have on welding by adding calcined borax, calcium carbonate and barium carbonate to the coating mixtures and also by changing the polarity. and found a curious phenomenon produced by barium carbonate.
(d) As the best condition, the writer obtained the following results: Each of the three kinds of mixtures of 6:4, 5:5, 4:6 of graphite and carborundum, and of 1% barium carbonate, -a substance which produced a curious phenomenon as mentioned in (c), was reduced to paste by the solution of water glass (1:3) and coated the same on electrodes, 33cm. long, 0, 49cm. diameter and 50gm. mean weight each, through a glass tube of 8mm. inner diameter. The electrode thus obtained is to be used, connected to the negative pole of the generator.
(e) Chemical analyses, microscopic examinations, hardness tests, bending tests and pressure tests were conducted on the deposits of the best condition. That we can obtain, without preheating, deposits of cast iron of various composition, with low sulphur, low phosphorus and no hard zone, is the merits of the electrodes prepared by the writer.

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