The Study of the Ageing Impact on Workability and Hardness of the Samples Made of Alloy VV751P (Ni-15Co-10Cr) after Selective Laser Sintering

Abstract

Work is focused on study of workability changing of heat resistant nickel-based Ni-15Co-10Cr alloy produced by selective laser sintering from metal powder. Experimental research of HRC hardness changing was provided on plate samples 2х10х30 mm after sintering and typical heat treatment for this alloy. Heat treatment was: annealing at temperature of 1,000oС during 1.5 hours, and then at the temperature of 1,180oC for 2.5 h – 3 h. After that samples were treated in a furnace for 50 – 60 minutes at the temperature of 1,050oС. Then they were cooled-off to the temperature of 1,000oС during 50 – 60 minutes. After that they were further quenched at ambient temperature. After quenching the samples were subjected to ageing at the temperature of 850oC during 3, 6, 9, 12 and 15 hours. The bending and measurement of triangle height was proposed for work ability assessment of samples. Increased hardness was found with duration of ageing. Work ability grew up with duration of ageing but where was a gap of workability for 9 hours ageing. Calibration of sintered parts and samples are recommended to perform after quenching and ageing at 850oC no longer 6 hours.