Abstract– In the present paper, the effect of heat treatment on the surface roughness of AISI 4140 steel has been investigated by use of paired t-test and one way analysis of variance (ANOVA). The paired t-test was performed to determine the differences between the means before and after heat treatment. One way ANOVA was used to further evaluate the effect of heat treatment on the difference in...

Achieving the mechanical properties of steels after various manufacturing and heat treatment processes is significant and essential. In production lines, after producing the specific and standard samples, mechanical properties have been measured by destructive processes which cause waste of cost and time. In addition, destructive techniques cannot detect the miniscule changes made in mechanical...

In this paper, the influence of heat treatment on PH17-7 stainless steel spring was evaluated. Precipitation hardening phenomenon of  PH 17-7 steel was evaluated in three stages. First, the spring constant changes with time and temperature was evaluated. Second, the spring constant changes with respect to its original length at constant temperature and time with blocking (spring length aft...

The objectives of this research were to find an economical way of reducing porosities in the microstructure of coatings deposited by flame spraying technique on CK45 steel and also trying to increase their cohesive strength to the substrate, so that the overall wear properties of this type of coating can be improved. So several specimens from this steel coated with NiCrBSi powder under specific...

The behaviour of the cryogenically treated En52 martensitic valve steel has been experimentally analyzed in this paper. Material samples are subjected to deep cryogenic treatment after completing the regular heat treatment. The critical properties of the valve steel like wear resistance, hardness, tensile strength and impact strength are evaluated for the cryo treated En52 valve steel samples a...