Department of Materials Processing, Graduate School of Engineering, Tohoku University, Sendai 980-8579, Japan.
Nanotechnology. 2012 Aug 10;23(31):315705. doi: 10.1088/0957-4484/23/31/315705. Epub 2012 Jul 13.
Multi-walled carbon nanotube (MWCNT) reinforced copper (Cu) matrix composites, which exhibit chromium (Cr) carbide nanostructures at the MWCNT/Cu interface, were prepared through a carbide formation using CuCr alloy powder. The fully densified and oriented MWCNTs dispersed throughout the composites were prepared using spark plasma sintering (SPS) followed by hot extrusion. The tensile strengths of the MWCNT/CuCr composites increased with increasing MWCNTs content, while the tensile strength of MWCNT/Cu composite decreased from that of monolithic Cu. The enhanced tensile strength of the MWCNT/CuCr composites is a result of possible load-transfer mechanisms of the interfacial Cr carbide nanostructures. The multi-wall failure of MWCNTs observed in the fracture surface of the MWCNT/CuCr composites indicates an improvement in the load-bearing capacity of the MWCNTs. This result shows that the Cr carbide nanostructures effectively transferred the tensile load to the MWCNTs during fracture through carbide nanostructure formation in the MWCNT/Cu composite.
多壁碳纳米管(MWCNT)增强铜(Cu)基复合材料在 MWCNT/Cu 界面处呈现出碳化铬(Cr)纳米结构,是通过使用 CuCr 合金粉末形成碳化物制备的。通过火花等离子烧结(SPS)和随后的热挤压,制备出完全致密且定向分布的 MWCNTs 分散在复合材料中的 MWCNT/CuCr 复合材料。MWCNT/CuCr 复合材料的拉伸强度随 MWCNTs 含量的增加而增加,而 MWCNT/Cu 复合材料的拉伸强度则低于单相 Cu。MWCNT/CuCr 复合材料拉伸强度的提高可能是由于界面 Cr 碳化纳米结构的载荷传递机制。在 MWCNT/CuCr 复合材料的断裂表面观察到的 MWCNTs 的多壁失效表明 MWCNTs 的承载能力得到了提高。这一结果表明,在断裂过程中,Cr 碳化纳米结构通过在 MWCNT/Cu 复合材料中形成碳化纳米结构,有效地将拉伸载荷传递到 MWCNTs 上。