TiC,TiB_2/铝熔体界面过渡区的研究

Transition Zone on the Interface of (TiC, TiB_2)/Aluminum Melt

研究了TiC,TiB2两种钛化物在纯铝熔体中的行为及其对熔体粘度的影响规律。720℃时的测量数据表明,以Al-5Ti-1B和Al-3Ti-0.15C形式加入微量TiB2或TiC的铝熔体,其粘度增加30%左右;分析了熔体粘度突变的原因,并提出了钛化物/铝熔体界面过渡区的假设。上述熔体经一段时间的保温后,出现了随熔体温度降低而粘度降低的异常变化,从钛化物/铝熔体界面过渡区的形成和整体的沉淀得到了合理的解释。固态条件下钛化物粒子周围存在Ti浓度的梯度分布也间接证实了熔体条件下钛化物/铝熔体界面过渡区的存在。

Influence of TiC or TiB2 on the viscosity of commercial pure Al melt as researched. The experimental results have indicated that the viscosity of the aluminum melt at 720degreesC increases by 30% or so after addition of a little amount of TiB2 or TiC in the form of Al-5Ti-1B or Al-3Ti-0.15C into the master alloys. Then a hypothesis of 'transition zone' on the interface between TiB2 (TiC) and aluminum melt has been put forward for analysis. An abnormal phenomena has been found that the melt viscosity decreases with the decrease of temperature. It can be explained from the forming of the 'transition zone' and the precipitation in the melt bewteen the compounds containing Ti and aluminum. The gradient distribution of Ti around TiC or TiB2 in the solid state can be also indirectly used to approve the existence of the 'transition zone' on the interface of TiB2 (or TiC) /aluminum in the melt state.