The molybdenum bar billet with diameter of 85 mm was prepared by cold isostatic pressure and sintering.Then the molybdenum bar with diameter of 32 mm was forged by different forging ways

and its microstructure and mechanical properties were tested comparatively.The results show that some parameters

such as the tempering temperature

tempering time

times of tempering and deformation rate in the forging process have effects on the microstructure and properties of the molybdenum bar after forging.The forging processing parameters were presented as follows:before forging

the blank of molybdenum bar kept at 1 200℃for 120 min.After that

the molybdenum bar was forged for six times.After each forging

the diameter deformation of molybdenum bar billet reached 10%to 20% of that before forging.During the whole forging process

intermediate tempering was carried out every two times.The temperature and time of intermediate tempering were 1 100℃for 15 min

respectively.Finally

the tensile strength and elongation of the molybdenum bar with fine and uniform structure reach 667 MPa and 26%

respectively.