Microstructure, mechanical properties and bonding characteristic of deformed tungsten

• Microhardness, strength, and toughness of tungsten were improved by addition of La2O3.
• The brittle-to-delamination transition temperature of WL10 is around 753 K.
• The rolled PW and WL10 were bonded with CuCrZr alloy by hot pressing method.
• Shearing/bending strength of PW/CuCrZr was higher than that of WL10/CuCrZr.
• The elongated La2O3 particles have a negative effect on bonding strength.

We focused on the microstructure, mechanical properties, and bonding characteristic of rolled pure tungsten (PW) and W-1.0 wt.%La2O3 (WL10). WL10 exhibited higher microhardness and bending strength despite lower density compared to PW. Charpy tests showed that WL10 displayed higher absorbed energies compared to PW at the same test temperatures, and the delamination fracture appeared at 873 K for WL10 while 1073 K for PW. However, the excellent mechanical properties of WL10 did not lead to high bonding strength when it was bonded with CuCrZr alloys. The shearing and bending strength are 122.26 and 183.91 MPa, lower than 198.69 and 215.27 MPa of PW. The difference of thermal–physical properties between tungsten and La2O3 caused the cracks near the interface, resulting in lower bonding strength of WL10.

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