Influence of Sn content on microstructure and properties of 304 stainless steel PM sintered body
Lü Wei1,WANG Tianguo1,HUA Jianjie2
(1. School of material science and engineering, Hubei University of Automotive Technology, Shiyan 442002, Chi‐
na;2. DongFeng Powder metallurgy Company of Dongfeng Motor Parts and Componenets Group Co., Ltd, Shi‐
yan 442002, China)
Abstract:304 austenitic powder metallurgy stainless steel was prepared by vacuum sintering, and the effects of
different Sn content on the microstructure, density, tensile strength and corrosion resistance of powder metallurgy
304 stainless steel were studied. The results show that at the sintering temperature of 1 300 ℃, with the increase of
Sn addition, the number of pores in the microstructure decreases, the pore size decreases and the distribution is uni‐
form, and the irregular large pores gradually become spherical small pores. The sample has a maximum density of
7.308 g/cm3. When the addition amount of Sn is 2%, the dimples of the sintered sample are evenly distributed, the
pores are spheroidized, the pores are small and uniform in size, and the dimples are connected in a network. The
mechanical properties are optimal, and the hardness and tensile strength reach 62.23HRB and 363.34 MPa, respec‐
tively. The mechanical properties reach the best, and the hardness and tensile strength reach 62.23HRB and 363.34
MPa respectively. With the increase of Sn addition, the mechanical properties also decrease due to the decrease of
density, and the dimple size in the fracture increases and irregular shapes appear. Electrochemical experiments
show that the corrosion resistance of 304 stainless steel increases first and then decreases with the increase of Sn
content to 2%.