Effect of Delta Current and Delta Current Frequency on tensile properties and microstructure of Gas Tungsten Constricted Arc (GTCA) welded Inconel 718 sheets

Journal of the Mechanical Behavior of Materials

Balasubramanian Visvalingam¹  Malarvizhi Sudersanan¹  Sonar Tushar¹  Sivakumar Dhenuvakonda²  Venkateswaran Thiruvenkatam² 

[1] Centre for Materials Joining and Research (CEMAJOR), Department of Manufacturing Engineering, Annamalai University, Annamalai Nagar-608002, Tamilnadu, ChidambaramIndia;Vikram Sarabhai Space Centre (VSSC), ISRO, Thiruvananthapuram695022, Kerala India;

关键词: gas tungsten constricted arcwelding;    delta current;    delta current frequency;    inconel 718 alloy;    tensile properties;    microstructure;   

DOI  :  10.1515/jmbm-2019-0020

来源: DOAJ

【 摘 要 】

Inconel 718 is a nickel-based superalloy which finds major applications in lightweight welded frames and other parts in gas turbine engines. This alloy is frequently joined by gas tungsten arc welding (GTAW) process for clean and precise welds. However, the weldability of Inconel 718 alloy is limited by the high heat input and slower cooling rate in GTAW process. It leads to the segregation of alloying elements and detrimental laves phase formation in weld metal which significantly reduces the tensile properties of the welded joints. To overcome this problem, a newly developed gas tungsten constricted arc welding (GTCAW) process is used for joining Inconel 718 alloy. The main effect of Delta Current (DC) and Delta Current Frequency (DCF) on the tensile properties and microstructure of GTCA welded 2 mm thick Inconel 718 alloy sheets was investigated. Superior tensile properties were exhibited at Delta Current of 50 A and Delta Current Frequency of 4 kHz due to the refinement in fusion zone. Delta Current and Delta Current Frequency showed deleterious effect at higher levels due to the high heat input.

【 授权许可】

Unknown