We study new biomedical alloys of the Ti–18Nb– x Si system with 0.6–1.2 wt.% Si both in the as-cast state and quenched in water after holding at temperatures from 800 to 1200°С. It is shown that their solid-solution hardening within certain temperature ranges is supplemented by dispersion hardening with silicides. Rapid cooling after melting promotes the formation of nonequilibrium partially quenched structures with dispersed secondary silicides and high hardness. Quenching at lower temperatures (800–1000°С) leads to an increase in the number and sizes of silicide precipitates and to the depletion of the solid solution of silicon as a result of which the level of hardness decreases. For high quenching temperatures (> 1100°С), the silicides are practically dissolved and the level of hardness also decreases. The temperature range 1050–1150°С proves to be optimal for the purposes of quenching of biocompatible alloys of the Ti–18Nb– x Si system.

中文翻译：

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硅化物的形成及其对用于生物医学目的的 Ti-18Nb-xSi 系统铸造合金结构和性能的影响

我们研究了具有 0.6-1.2 wt.% Si 的 Ti-18Nb-x Si 系统的新型生物医学合金，无论是铸态还是在 800 至 1200°С 的温度下保持后在水中淬火。结果表明，它们在一定温度范围内的固溶硬化由硅化物的弥散硬化补充。熔化后的快速冷却促进了具有分散的二次硅化物和高硬度的非平衡部分淬火结构的形成。在较低温度（800-1000°С）下淬火会导致硅化物沉淀物的数量和尺寸增加，并导致硅的固溶体耗尽，从而导致硬度水平降低。对于高淬火温度（> 1100°С），硅化物实际上溶解，硬度水平也降低。