机械合金化19Cr-14Ni不锈钢粉末激光熔覆层的组织和性能

Microstructure and Properties of Laser Cladded Coating of Mechanical Alloying Powders of 19Cr-14Ni Stainless Steel Power

激光熔覆所用粉末材料的制备方法主要是雾化法。为探索激光熔覆专用材料的制备新方法,将以单元素粉末的形式,按照19Cr-14Ni不锈钢的成分来配制混合粉,并将该混合粉机械合金化45h,在45#钢板上分别将采用上述两种不锈钢粉末进行激光熔覆。采用X射线衍射(XRD)、扫描电镜(SEM)/能谱仪(EDS)、腐蚀电化学等方法研究熔覆层的相组成、微结构和耐蚀性。结果表明,与雾化粉体激光熔覆层相比,机械合金化粉体激光熔覆层的枝晶得到细化,其组织呈连续网状分布,Cr元素的枝晶间偏析得以改善;与雾化粉体相比,机械合金化能提高粉体熔覆层的耐蚀性能,但其硬度略有降低。

Generally, the powders that used in laser cladding are atomized. To explore new technology the powders used for laser cladding, atomized powders of 19Cr-14Ni type of stainless steel （mixed by element powders） are mechanically alloyed for 45 h. Then, the two kinds of powders are cladded on 45# steel. Finally, X-ray diffraction （XRD）, scanning electron micrscope （SEM）/energy dispersive spectroscopy （EDS） and electrochemical methods are utilized to investigate the phases composition, microstructure and corrosion behavior of the two laser cladded coatings method. The results show that the grains of laser cladded coating with mechanical alloying （MA） powders are much finer than that of the coating with atomized powders. Due to the formation of net-like structure and the decrease in Cr element segregation between dendritic crystals, the However, its microhardness is slightly decreased.