Structure and properties of welded joint of high-strength wear-resistant steel NM360

Abstract

Present research studies the structure and properties of welded joint of high-strength wear-resistant steel NM360 by means of carbon dioxide arc welding with welding material GFM-70. The experimental result indicates that high-strength wear-resistant steel NM360 can be welded together with appropriate welding parameters. In the whole joint area, macroscopic defect such as pore, inclusion and crack does not appear. The joint tensile strength exceeds that of welding material GFM-70 at least 10.5%. The impact energy in each part of joint doubles that of base metal. Between the joint and base metal, there is coarse grain zone, fully recrystallised zone, incompletely recrystallised zone. The hardness in heat affected zone and near fusion line is quite large, which distributes in the range of 360–394 HV. The hardness of other area in joint is smaller than that of base metal NM360.

Keywords:

• Wear-resistant steel
• Welded joint
• Structure
• Properties

Additional information

Funding

The research work is supported by the Doctoral Foundation of Henan Polytechnic University (No. B2014–006) and Key Scientific Research Project of Colleges and Universities in Henan Province (No. 15A430007).