Reduction and decarburization during the annealing of atomized cast iron powder with converted gas in brovary powder metallurgy factory industrial furnaces

Conclusions An investigation into kinetics of reduction-decarburization annealing in industrial reduction furnaces employing a converted gas (CO₂/CO = 0.41 and 7–9% H₂O) countercurrent has demonstrated that, to obtain satisfactory and stable results in a short time of annealing at 900–1000°C with an atomized cast iron powder of O/C ratio 1.9–2.2, the heating of the powder to the required annealing temperature should be performed at a rate not exceeding 9 deg C/min.Translated from Poroshkovaya Metallurgiya, No. 11(179), pp. 90–92, November, 1977.     

Simulation of processes of high-temperature gas corrosion of titanium alloys in vacuum

A physicomathematical model of the process of high-temperature interaction of titanium alloys of the system Ti-Al-Mn in a rarefied medium has been considered that takes into account gas saturation of the metal and sublimation of the alloying element. The example of the alloy OT4-1 illustrates the fact that the model representations and the experimental data are in satisfactory agreement. The model representations can be apparently extended also to other types of alloys. The model can be used for expert estimation of the effect of a vacuum in the heat treatment or the utilization of titanium alloys.Translated from Fiziko-Khimicheskaya Mekhanika Materialov, Vol. 26, No. 6, pp. 29–34, November–December, 1990.     

Uniform Elongation and the Stress-Strain Flow Curve of Steels Calculated from Hardness Using Empirical Correlations

An empirical relationship between the hardness and uniform elongation of non-austenitic hypoeutectoid steels has been developed. This new hardness-elongation relationship was combined with previously developed correlations of hardness and strength (yield and ultimate tensile strength) to predict the stress-strain flow curve from a single hardness test. The current study considers both power law hardening behavior and exponential hardening behavior. Reasonable agreement was observed between the experimental and predicted flow curves of a high strength, low alloy steel. Additionally, an empirical correlation of the flow strength at instability with hardness is provided.