Material combination的用法和样例：
例句
- Polymer ball bearings can be made from a variety of materials and material combinations.
聚合物球轴承可由多种材料和材料组合制造。 - RC is a composite material with rebar and concrete that have different physical mechanics characters, and its constitutive relationship is relatively complex.
摘要钢筋混凝土是由钢筋和混凝土两种具有不同物理力学性质的材料组合而成的复合材料，其本构模型比较复杂。
