镍对铁基激光快速成型试件组织与力学性能的影响

Effect of nickel on microstructure and mechanical properties of Fe-based laser rapid prototyping sample

利用激光快速成型技术在Q235基材上熔覆3种镍含量（1.5%~2.5%、2.5%~3.5%和4.5%~5.5%,质量分数）的不锈钢粉末。利用XD-3型X射线衍射仪、TH320型洛氏硬度计、WDW-20E型万能试验机、OLYMPUS GX51F型光学显微镜和JSM-6701F型扫描电镜研究了3种不锈钢粉末试件的显微组织和力学性能。结果表明,随着镍含量的增加,激光快速成型试件熔覆层中残留奥氏体含量逐渐增多,平均晶粒尺寸变大。试件的硬度和抗拉强度逐渐下降,试件的拉伸断裂方式由脆性断裂变为塑性断裂。

After the stainless steel powder with different nickel content（ 1. 5%-2. 5%,2. 5%-3. 5% and 4. 5%-5. 5%,mass fraction） being deposited on Q235 substrate by the laser rapid prototyping technology,the microstructure and mechanical properties of these stainless steel samples were studied by using XD-3 X-ray diffractometer, TH320 Rockwell hardness tester, WDW-20 E universal testing machine,OLYMPUS GX51 F optical microscope and JSM-6701 F scanning electron microscope. The results show that with the increase of nickel content,the content of retained austenite in the laser cladding layer increases gradually,the average grain size becomes larger,the hardness and tensile strength of the samples decrease gradually,and the tensile fracture mode changes from brittle fracture to plastic fracture.