Ti3 AL-Nb-Mo composites were prepared by SHS using initial powder mixtures of Ti-Al-Nb-Mo and their corrosion and mechanical properties were studied to develop bioand environmental materials. The composites reached 99...Ti3 AL-Nb-Mo composites were prepared by SHS using initial powder mixtures of Ti-Al-Nb-Mo and their corrosion and mechanical properties were studied to develop bioand environmental materials. The composites reached 99.8% of theoretical density after the direct consolidation. The composites shows equiaxed primary a2 in a matrix of fine secondary a2 plates and ordered 82 (Bo) forming a basket weave structure. The strain rate sensitivity (m = dlnσ/dlne) at 2% strain is 0.008. Corrosion potential and corrosion rate of the composites formed by SHS were -151. 5m VSHE and 5. 72× 10^(-8)A/cm2 for Ti3 Al-10Nb-1. 5Mo and - 138.4m VSHE and 4. 12×10^(-8)cm2 for Ti3 Al-12Nb-1.5Mo in a 50% NaOH-10%FeCI3 solution, respectively. Corrosion resistance decreased with niobium content in the composites and chloride content in the aqueous solution. Selective corrosion of a2 phase in a matrix occurred in the corrosion environment which suggests that the corrosion potential and rate changes are related to the niobium content and Q2 phase in a matrix.展开更多
文摘Ti3 AL-Nb-Mo composites were prepared by SHS using initial powder mixtures of Ti-Al-Nb-Mo and their corrosion and mechanical properties were studied to develop bioand environmental materials. The composites reached 99.8% of theoretical density after the direct consolidation. The composites shows equiaxed primary a2 in a matrix of fine secondary a2 plates and ordered 82 (Bo) forming a basket weave structure. The strain rate sensitivity (m = dlnσ/dlne) at 2% strain is 0.008. Corrosion potential and corrosion rate of the composites formed by SHS were -151. 5m VSHE and 5. 72× 10^(-8)A/cm2 for Ti3 Al-10Nb-1. 5Mo and - 138.4m VSHE and 4. 12×10^(-8)cm2 for Ti3 Al-12Nb-1.5Mo in a 50% NaOH-10%FeCI3 solution, respectively. Corrosion resistance decreased with niobium content in the composites and chloride content in the aqueous solution. Selective corrosion of a2 phase in a matrix occurred in the corrosion environment which suggests that the corrosion potential and rate changes are related to the niobium content and Q2 phase in a matrix.
