(1. 北京交通大学 机械与电子控制工程学院，北京 100044；
2. 河北科技大学 材料科学与工程学院， 石家庄 050054)
摘 要: 通过对半固态合金流变充型过程的物理分析， 结合半固态合金包含圣维南体和假塑性体的流变特性， 根据充型驱动力大于或等于充型阻力， 阻流通道内不可流动层厚度小于阻流截面最小厚度的1/2这两个充型临界条件， 运用不可压缩粘性流体流动理论， 建立半固态合金充满型腔获得完整零件的两个临界条件的数学表达式。 为了验证其准确性， 对钩舌、 轴箱体零件进行了流变成形实验， 实验结果证实该临界条件数学表达式的正确性。 该式包含设备参数、 工艺参数、 材料参数和模具参数， 可用来指导半固态流变成形工艺设计、 设备选型， 并能进行缺陷预测和充型过程控制。
关键字: 半固态合金； 充型阻力； 阻流通道； 临界条件
（1. School of Mechanical and Electronic Control Engineering,
Beijing Jiaotong University, Beijing 100044, China;
2. School of Materials Science and Engineering, Hebei University of
Science and Technology, Shijiazhuang 050054, China）
Abstract: By the physical analysis about the rheological filling process of semi-solid alloy, based on the rheological characteristic of semi-solid alloy which includes saint venant body and pseudoplastic, according to the two filling critical conditions that the driving force of mold filling is greater than mold filling resistance and the thickness of non-flowing layer in the channel of resistance to flow is thinner than a half of the minimum of the channel section, managing the flow theory about incompressible viscous fluid, the mathematic representations of the two critical conditions that the cavity can be filled with semi-solid alloy to obtain the perfect casting were deduced. In order to demonstrate the accuracy of the criterion condition, the rheoforming experiment of the hook-head casting and axle box boby casting is carried out. The result of the experiment shows the accuracy of the criterion condition. The mathematic representation includes the equipment parameters, processing parameters, material parameters and mould parameters. It can be used to instruct the technological design and equipment selection about the semi-solid rheoforming. Moreover, it also can be used to forecast flaw and control filling process.
Key words: semi-solid alloy; mold filling resistance; channel of resistance to flow; critical condition
