【摘要】 在激光扫描涂覆Al-Ti-C活化粉料层的铝合金试样过程中,突然停止激光发射,以在激光束前面形成合成反应过程中不同阶段所产生的组织,判断所发生的化学反应,即先发生3Al+Ti→Al3Ti反应,形成块状Al3Ti;以后再发生Al3Ti+C→TiC+3Al反应,形成大量TiC颗粒。将实验与数值模拟相结合,采用试错法求得:3Al+Ti→Al3Ti的反应温度为650℃,Al3Ti+C→TiC+3Al的反应温度为810℃。更多还原

【Abstract】 In the experiment, Al specimen coated with a layer of activated Al Ti C powder mixture was scanned by a laser beam. In order to remain the microstructures in the surface region ahead of laser spot, the laser emission was broken off during the scanning. The microstructures of different distances from laser spot were composed of the products formed in different stages of synthesis reaction. According to the constituents in the microstructures, the following conclusions can be deduce: firstly, the reaction 3Al+Ti→Al3Ti occurs and forms block like structure of Al3Ti, and then the reaction Al3Ti+C→TiC+3Al takes place and produces a mass of TiC spherules. Combining the experiment with numerical simulation of temperature field and using trial and error procedure, the reaction temperatures are determined as follows: it is 650°C for reaction 3Al+Ti→Al3Ti, and 810°C for Al3Ti+C→TiC+3Al.更多还原