选择性激光熔化制备纯钨的性能研究

Study on the Properties of Pure Tungsten Produced by Selective Laser Melting

摘要:

以粒度集中的纯钨粉末为原料,通过选择性激光熔化技术(Selective Laser Melting)制备样品,分别经过1000℃、1400℃以及1960℃的热处理2h。研究不同相对密度和不同高温处理后样品的力学性能和显微组织,并采用X射线衍射(XRD)表征其微观结构。结果表明：纯钨样品的相对密度处于 75%~95%之间,其抗弯强度和显微硬度随相对密度的增加而增大,显微组织大体相似。经不同高温处理后,在1400℃处理后样品达到了最佳的力学性能,1960℃处理后样品的晶粒发生了明显的长大现象,材料力学性能降低。XRD图谱结果表明,SLM制得样品与其经过1960℃烧结后,其晶体结构并未发生改变。

Abstract:

Pure tungsten powder of which the particle size distributed intensively is processed to different samples by selective laser melting(SLM). Then, the samples are preserved in temperature of 1000℃, 1400℃ and 1960℃ for 2h. The mechanical property and microstructure of the samples of different densities and different heat treatment temperatures are studied. The morphology and microstructure are characterized by SEM and XRD respectively. Result shows that the density ratios of the pure tungsten sample vary from 75% to 95%. Bending strength and microhardness increase with the raise of the density, but the microstructure difference between these samples is not obvious. After the heat treatment under different temperature, the mechanical property of the sample by 1400℃ treatment is better than other samples. Under 1960℃ heat treatment, the grain size of pure tungsten sample raises, leading to the decrease of mechanical property. The XRD result demonstrates that the grain structure of the pure tungsten sample does not change after 1960℃ heat treatment.