Effects of Powder Size on the Surface Quality,Microstructure and Mechanical Properties of Co-Cr-W Alloy by Selective Laser Melting
The quality of metallic powder plays an important role in selective laser melting(SLM)process,the chemical composition,impurity content,morphology and size distribution of the powder influent the microstructure and mechanical properties of SLM parts.In this paper,the gas atomized Co-Cr-W powders with two different size distributions,10-53μm and 10-30μm,were employed to study the effect of size distribution on the phase formation,microstructure and mechanical properties of SLM alloy.The results show that,both powders are compatible to SLM process for their low impurity,high sphericity and good flowability.During the SLM process,the microstructure transforms partially from γ-fcc to ε-hcp to form a typical dual-phase structure.The tensile strength of as-SLM samples from both powders show no apparent differences while as-SLM samples by the powder with narrow size distribution possesses larger elongation.Compared with the sample from wide-size-distribution powder,the strength of the sample from narrow-size-distribution powder decreases more significantly after solution treatment,accompanied by a larger increase of elongation.Both samples exhibit higher strength while lower elongation by aging treatment.It indicates that,high strength can be obtained by using wide-size-distributed powder,while large elongation by using narrow-size-distribution powder.Both powders meet the requirements of commercial applications.
Selective laser melting Co-Cr-W alloy Powder size Microstructure Mechanical properties
Li Kefeng Mao Xinhua Liu Xin Zou Liming
Guangdong Institute of Materials and Processing,Guangdong Academy of Sciences,Guangzhou 510650,Guangdong,China;National Engineering Research Center of Powder Metallurgy of Titanium & Rare Metals,Guangzhou 510650,Guangdong,China
国际会议
北京
英文
1595-1601
2018-09-16（万方平台首次上网日期，不代表论文的发表时间）