corresponding relationship of 38CrMoAl screw barrel

matrix hardness with nitriding performance

 

 

PAN Yuan

 

(Zhoushan Institute of Calibration and Tseting for Quality and Technology Supervision, Zhoushan 316021, China)

 

 

Abstract: Aiming at the problem of matrix hardness control of 38CrMoAl screw barrel nitriding layer, the matrix hardness and the surface hardness, hardness gradient and depth determination of 38CrMoAl screw barrel nitriding layer were studied. After the analysis of 38CrMoAl screw barrel nitriding layer measurement examples, the corresponding relation between matrix hardness and nitriding layer was established. Based on the formation mechanism and control of matrix hardness, the control range and the lower limit value of the matrix hardness of the 38CrMoAl screw barrel nitriding layer were proposed. The results indicate that, the properties of matrix hardness and nitriding layer has a corresponding relationship, matrix hardness is mainly determined by quenching and tempering hardness, hardness is controlled in 250HBW~300HBW which can solve the shortage of nitriding, nitriding depth being shallow and improve the hardness gradient of the nitrided layer, in the depth measurement of the nitriding layer, the lower limit value of the matrix hardness is set to 250 HV with suitable.

 

Key words: screw barrel; matrix hardness; nitriding layer; depth; determination