Effect of P-MIG and CMT on microstructure and properties of 6082-T6 joints

Abstract

This paper focuses on pulse metal inert gas welding (P-MIG) and cold metal transfer (CMT) of 6082-T6 aluminium alloy. The microstructure and properties of joints were analysed and the phase transformation of the welding zones (WZ) was calculated using JMatPro. The results showed that CMT joints are better than P-MIG joints in tensile strength and hardness. The main reason is that the average grain size and the second phase size of CMT joints are smaller than those of P-MIG joints. Moreover, the larger number of large-angle grain boundaries (LAGB), diffusely distributed Al₃Mg₂ and Al₆Mn phases in CMT WZ, as well as a small amount of distributed Al₃Zr, are beneficial to the joints properties too.

KEYWORDS:

• 6082-T6 aluminium alloy
• P-MIG welding
• CMT welding
• mechanical property
• microstructure
• JMatPro

Disclosure statement

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

Data availability

1. The author promises that the data and materials in the article are true and reliable. The author promises that the work described is original research that has not been published before, and does not consider publishing in whole or in part elsewhere. The author ensures objectivity and transparency in research and to ensure that accepted principles of ethical and professional conduct have been followed.

2. The author promises the availability of the JMatPro software and has the right to use the genuine JMatPro software.

Additional information

Funding

The work was supported by the Key Science and Technology Project of Yunnan Province (Grant number 202002AB080001-4), the Key Research & Development Program of Yunnan Province & Development Program of Yunnan Province (Grant numbers 202103AA080017), and the Basic Research Project of Yunnan Province (Grant number 202201AU070081).