Semisolid State Sintering Behavior of Aluminum⁻Stainless Steel 316L Composite Materials by Powder Metallurgy.

Kwangjae Park,Kyungju Kim,Dasom Kim,Kenta Takagi,Hansang Kwon,Seungchan Cho

doi:10.3390/ma12091473

Abstract

Aluminum (Al)-stainless steel 316L (SUS316L) composites were successfully fabricated by the spark plasma sintering process (SPS) using pure Al and SUS316L powders as raw materials. The Al-SUS316L composite powder comprising Al with 50 vol.% of SUS316L was prepared by a ball milling process. Subsequently, it was sintered at 630 °C at a pressure of 200 MPa and held for 5 min in a semisolid state. The X-ray diffraction (XRD) patterns show that intermetallic compounds such as Al13Fe4 and AlFe3 were created in the Al-SUS316L composite because the Al and SUS316L particles reacted together during the SPS process. The presence of these intermetallic compounds was also confirmed by using XRD, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and EDS mapping. The mechanical hardness of the Al-SUS316L composites was analyzed by a Vickers hardness tester. Surprisingly, the Al-SU316L composite exhibited a Vickers hardness of about 620 HV. It can be concluded that the Al-SUS316L composites fabricated by the SPS process are lightweight and high-hardness materials that could be applied in the engineering industry such as in automobiles, aerospace, and shipbuilding.

Highlights

High-performance materials are required in various sectors of the engineering industry such as in aerospace applications, engineering of robots, and in automobile manufacture [1,2,3]
We proposed that the Al-SUS316L composite could be fabricated in a semisolid state by sintering process (SPS)
We have investigated a semisolid state sintering process that allows the creation of a small amount of a liquid phase

Summary

Introduction

High-performance materials are required in various sectors of the engineering industry such as in aerospace applications, engineering of robots, and in automobile manufacture [1,2,3]. Aluminum alloys are used in various industrial fields because of their excellent processability. They are corrosion resistant due to the formation of a thin surficial aluminum oxide film. Stainless steel has a higher mechanical strength than aluminum It has a higher density (7.9 g cm−3 ) and it is more expensive. Composites fabricated by mechanical ball milling and SPS in the solid state. We proposed that the Al-SUS316L composite could be fabricated in a semisolid state by SPS. We have fabricated an Al-SUS316L composite with high Al or SU316L content using mechanical ball milling and SPS. Fabrication of semisolid state sintering with high Al or SUS316L content is not commonly reported. We have shown that the Al-SUS316L composites combine the advantages both Al and SUS316L

Materials and Methods

Results and Discussion

Photograph mold of of semisolid semisolid sintered sintered Al-SUS316L

Conclusions