Study of joint microstructural properties of ZrC/Al-Mg composites-enhanced AA7075

ABSTRACT

In this study, the ZrC_p/Al-Mg composite fillers, successfully prepared using semi-solid stir casting, ultrasonic vibration and multi-pass rolling processes, were joined with 7075-T651 plates via tungsten insert gas (TIG) welding. The metallographic structure, tensile strength, microhardness and corrosion resistance were investigated. The results indicated that the introduction of ZrC particles favoured the continuous heterogeneous nucleation and inhibit the formation of coarse precipitates in the composite materials. The uniform distribution of ZrC particles could refine α-Al grains. As a result, the mechanical properties and corrosion resistance of weld joints were improved compared to those with 5183 fillers. Study turned out the optimal amount of ZrC particles was 2 wt.%, improving significantly on grain size, tensile strength, corrosion resistance and microhardness.

KEYWORDS:

• ZrC particles
• multi-pass rolling
• microstructure morphology
• mechanical properties
• corrosion resistance
• TIG welding

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by Science and Technology Major Project of Guangxi, China (No. AA17129005), and Collaborative Innovation Center for Exploration of NonferrousMetal Deposits and Efficient Utilization of Resources,GuilinUniversity of Technology, China.