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[Display omitted] • Cu-Nb composite diffused metal interlayer was first applied to TC4 and 4J36 electron beam welding. • The use of Cu-Nb interlayer produces solid solutions in the two weld melting zones. • The use of Cu-Nb interlayer improves the quality of welded joint between TC4 and 4J36. • The formation mechanism of 4J36/Cu-Nb/TC4 bonded joints was studied. Electron beam welding of 4J36 invar alloy and TC4 titanium alloy was carried out with Cu-Nb composite diffused metal interlayer. The results showed that the depth to width ratio and the tensile strength of welded joints increased with the increase of electron beam current. Under the designed process parameters, two melting zones (MZ) in welded joints formed solid solutions (ss), the welded joint tensile strength reached maximum value of 244.1 MPa, and the fracture location was mainly located at 4J36/Cu interface. [ABSTRACT FROM AUTHOR]

Ultrasonic vibration (UV) treatment has been successfully applied to improve the particles distribution of nano-sized SiC particles (SiC p ) reinforced Al-5Cu alloy matrix composites which were prepared by combined processes of dry high energy ball milling and squeeze casting. When UV treatment is applied, the distribution of nano-sized SiC p has been greatly improved. After UV for 1 min, large particles aggregates are broken up into small aggregates due to effects of cavitation and the acoustic streaming. After UV for 5 min, all the particles aggregates are dispersed and the particles are uniformly distributed in the composites. Compared with the Al-5Cu matrix alloy, the ultimate tensile strength, yield strength and elongation of the 1 wt% nano-sized SiC p /Al-5Cu composites treated by UV for 5 min are 270 MPa, 173 MPa and 13.3%, which are increased by 7.6%, 6.8% and 29%, respectively. The improvements of mechanical properties after UV are attributed to the uniform distribution of nano particles, grain refinement of aluminum matrix alloy and reduction of porosity in the composites. [ABSTRACT FROM AUTHOR]

A biomedical β titanium alloy (Ti–7Nb–10Mo) was designed and prepared by vacuum arc self-consumable melting. The ingot was forged and rolled to plates, followed by quenching and aging. Age-hardening behavior, microstructure evolution and its influence on mechanical properties of the alloy during aging were investigated, using X-ray diffraction, transmission electron microscopy, tensile and hardness measurements. The electrochemical behavior of the alloy was investigated in Ringer's solution. The microstructure of solution-treated (ST) alloy consists of the supersaturated solid solution β phase and the ω ath formed during athermal process. The ST alloy exhibits Young's modulus of 80 GPa, tensile strength of 774 MPa and elongation of 20%. The precipitation sequences during isothermal aging at different temperatures were determined as β + ω ath → β + ω iso (144 h) at T aging = 350–400 °C, β + ω ath → β + ω iso + α → β + α at T aging = 500 °C, and β + ω ath → β + α at T aging = 600–650 °C, where ω iso forms during isothermal process. The mechanical properties of the alloy can be tailored easily through controlling the phase transition during aging. Comparing with the conventional Ti-6Al-4 V alloy, the Ti–7Nb–10Mo alloy is more resistant to corrosion in Ringer's solution. Results show that the Ti–7Nb–10Mo alloy is promising for biomedical applications. [ABSTRACT FROM AUTHOR]