Laser engineered net shaping (LENS™) allows for the deposition of novel hybrid materials with microstructures composed of solid solution and precipitation strengthened metallic matrices, along with a distribution of reinforcing in situ formed hard ceramic and solid lubricant phases. In this study, four different composites in the Ni-Al-Cr-C system were fabricated via LENS™ as potential candidate materials for high temperature wear resistant components. Microstructural evolution during solidification and sliding wear were studied at room and elevated temperatures. Experimental and solution thermodynamic simulations were used to evaluate the evolution of various compositions of hard chromium carbides and solid lubricant graphite dispersed into a continuous γ/γ′ (L1₂) matrix. By tailoring the microstructures along the build direction, desired hardness and wear properties were achieved for the different Ni-Al-Cr-C composites. Specifically, compositional modification of chromium and carbon were determined to drastically affect the corresponding phase morphology and properties. The two lowest wear rates measured were for the Ni-14Al-9Cr-29 C (at%) composite at 500 °C and Ni-12Al-3Cr-45 C (at%) composite at room temperature. Mechanistic studies using surface and subsurface scanning and transmission electron microscopies in the wear surfaces revealed this was a result of a combination of increased hardness/load-bearing and formation of tribochemical protective oxide glaze layers.

激光工程网成形（LENS™）可以沉积具有由固溶体和沉淀增强的金属基体组成的微结构的新型混合材料，以及在原位形成的硬质陶瓷相和固体润滑剂相的分布。在这项研究中，通过LENS™制造了Ni-Al-Cr-C系统中的四种不同的复合材料，作为高温耐磨组件的潜在候选材料。在室温和高温下研究了凝固和滑动磨损过程中的微结构演变。使用实验和溶液热力学模拟来评估分散到连续γ/γ'（L1 ₂） 矩阵。通过沿构造方向调整微观结构，可以对不同的Ni-Al-Cr-C复合材料实现所需的硬度和耐磨性。具体而言，确定了铬和碳的成分修饰，以极大地影响相应的相形态和性能。测得的两个最低磨损率是在500°C的Ni-14Al-9Cr-29 C（at％）复合材料和在室温下的Ni-12Al-3Cr-45 C（at％）复合材料。在磨损表面中使用表面和亚表面扫描以及透射电子显微镜进行的机械研究表明，这是硬度/承载力增加和摩擦化学保护性氧化釉层形成的结果。