Grain refinement in aluminum alloyed with titanium and boron
Grain refinement in aluminum alloyed with titanium and boron
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DOI：
10.1007/bf02663335
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发表时间：
1971-02
期刊：
影响因子：
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通讯作者：
J. Antonio;L. Lfo
中科院分区：
文献类型：
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作者：
J. Antonio;L. Lfo
对三元Al-B-Ti相图的铝角进行了探索。共晶：Liq-Al + TiAl 3+（Al，Ti）B2，在约0.05 wt % Ti，0.01 wt %B; 659.5 ℃时被发现. TiB 2和A1 B2形成连续的固溶体系列，但没有发现明显的三元相，硼的加入使TiAl 3的初晶区向低钛含量方向扩展，液相线变陡。在平衡条件下，只有在以TiAl 3为主并在任何其他杂质起作用之前使铝固溶体成核的合金中才能发现明显的晶粒细化。包封反应促进了这种优先性，但它不是晶粒细化所必需的。由于钛和硼在铝中的扩散率低，很少达到平衡，在工业实践中，还发现在其初次结晶的平衡场之外，通过TiAl 3进行晶粒细化。
The aluminum corner of the ternary Al-B-Ti diagram was explored. A eutectic: Liq — Al + TiAl3+ (Al, Ti)B2was found at approximately 0.05 wt pct Ti, 0.01 wt pct B; 659.5‡C. TiB2and A1B2form a continuous series of solid solutions, but no distinct ternary phase was found. The addition of boron to aluminum-titanium alloys expands the field of primary crystallization of TiAl3toward lower titanium contents and steepens the liquidus. In equilibrium conditions, pronounced grain refinement is found only in alloys in which TiAl3is primary and nucleates the aluminum solid solution before any other impurity can act. The peritectic reaction facilitates this priority but it is not necessary for grain refinement. Because of the low diffusivity of titanium and boron in aluminum, equilibrium is seldom attained and in commercial practice grain refinement by TiAl3is found also outside its equilibrium field of primary crystallization.