THE HOT DEFORMATION BEHAVIOR OFSPRAY-FORMED HIGH SPEED STEEL

Shunli Zhao,
 
Junfei Fan,
 
Jieyu Zhang,
 
Kuochih Chou
 

Powder Metallurgy - Kiev: Frantsevich Institute for Problems of Materials Science NASU, 2017, #01/02
http://www.materials.kiev.ua/article/2306

Abstract

The hot deformation behavior of spray-formed 1.28C–6.4W–5Mo–4.2Cr–3.1V–8.5Co high speed steel is investigated in the 950–1100 °C temperature range at a strain rates of 0.1 to 50 sec–1 and a true strain of 1.0. The activation energy for hot deformation is obtained. The relation between the flow stress and Zener–Hollomon parameter is successfully analyzed via the hyperbolic sine function under the whole range of deformation conditions. By a microstructural analysis for the breakdown of carbide networks in the temperature range and different strain rates, the size and distributing character of carbide grains are given. The appropriate ranges of deformation temperature and strain rate are provided to obtain fine spheroidal carbideparticles and their uniform distribution.


CARBIDE, FLOW STRESS, HOT DEFORMATION, SPRAY PROCESS, STAINLESS STEELS, STRAIN RATE