Microstructure and mechanical properties of electron beam welded joints of tantalum and GH3128
| Autor: | Longcan Ding, Sang Sang, Dong Li, Yunlong Tang, Qi Xiong, Chaoran Wang |
|---|---|
| Rok vydání: | 2019 |
| Předmět: |
010302 applied physics
Materials science Mechanical Engineering Butt welding 02 engineering and technology Welding 021001 nanoscience & nanotechnology Condensed Matter Physics Microstructure 01 natural sciences Indentation hardness law.invention Mechanics of Materials law 0103 physical sciences Ultimate tensile strength Fracture (geology) General Materials Science Composite material 0210 nano-technology Joint (geology) Beam (structure) |
| Zdroj: | Materials Science and Engineering: A. 768:138431 |
| ISSN: | 0921-5093 |
| DOI: | 10.1016/j.msea.2019.138431 |
| Popis: | The butt welding of Ta and GH3128 plates of 1.5 mm thick by using electron beam is conducted. The effects of the beam offset on the microstructure, defects, mechanical properties and fracture characteristics of the joint are studied. The results show that during direct welding, the major defects in Ta/GH3128 joint are penetrating cracks and gas pores, and the weld is mainly made up of columnar grains. The microhardness of the weld greatly changes and the maximum appears at the fusion line of Ta side. Tensile strength of the welded joint is only 150 MPa. The fracture location occurs near the Ta side by the fusion line, which shows the characteristics of brittle fracture. However, the defect-free sound joint is obtained under the condition of 0.5 mm beam offset to Ta. The microstructure of the weld is turned from the columnar grains into the equiaxial crystals. Hardness of the joint is obviously higher than that of the directly welded joint. Tensile strength of the joint is improved to 277 MPa via a 0.5 mm beam offset to Ta. The explanation for why the welded joint is strengthened under the condition of 0.5 mm deviated to the Ta side is given. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect