轧膜成形制备W-Cu层状功能梯度材料及其性能研究

以W粉和电解Cu粉为原料,聚乙烯醇缩丁醛(PVB)为粘结剂,通过有机基轧膜工艺制备出3种组成的单层生坯(Cu质量分数分别为25%、50%、75%),再叠层共轧,制备出了具有不同粘结剂含量的W-Cu层状梯度材料生坯,之后在H2气氛中烧结,获得了W-Cu层状梯度材料,考察了粘结剂含量与制备工艺条件对材料显微组织和性能的影响。结果表明,通过单层轧制、叠层共轧共烧可以制得层状梯度W-Cu复合材料;粘结剂含量对W-Cu层状梯度材料的致密度和性能有着明显的影响。当粘结剂质量分数为6%时,轧膜坯有较好的成形性,且成形坯的孔隙率较低;所得多层生坯经1 150℃烧结后相对密度达93.11%;所得梯度W-Cu材料有良好的物理、力学性能。

Fabrication and properties of W-Cu functionally graded materials by tape calendaring method

With tungsten powder and electrolytic copper powder as raw materials and PVB as the binder,W-Cu green tapes with different Cu contents (W-25%Cu,W-50%Cu,W-75%Cu,mass percent) were prepared by a tape calendaring method. Green W-Cu graded tapes were obtained by laminating the three W-Cu tapes together,and were subsequently sintered in H2 atmosphere to form W-Cu graded samples. Influence of the binder content on the green tapes was investigated. The formability,microstructure and physical properties were also investigated to evaluate the effect of processing conditions on the sintered W-Cu graded samples. The results indicate that W-Cu composite materials with layered structures can be successfully fabricated by a process based on tape calendaring and lamination. The binder content has an obvious effect on the density and properties of the W-Cu graded materi-als,and the green tapes with 6%(mass percent) binder show better formability and lower porosity. The W-Cu com-posite materials with layered structures sintered at 1150 ℃ have a relative density of 93.11%. The resultant W-Cu graded materials have excellent physical and mechanical properties.