State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an 710049, China.
Nat Mater. 2013 Apr;12(4):344-50. doi: 10.1038/nmat3544. Epub 2013 Jan 27.
The high-temperature stability and mechanical properties of refractory molybdenum alloys are highly desirable for a wide range of critical applications. However, a long-standing problem for these alloys is that they suffer from low ductility and limited formability. Here we report a nanostructuring strategy that achieves Mo alloys with yield strength over 800 MPa and tensile elongation as large as ~ 40% at room temperature. The processing route involves a molecular-level liquid-liquid mixing/doping technique that leads to an optimal microstructure of submicrometre grains with nanometric oxide particles uniformly distributed in the grain interior. Our approach can be readily adapted to large-scale industrial production of ductile Mo alloys that can be extensively processed and shaped at low temperatures. The architecture engineered into such multicomponent alloys offers a general pathway for manufacturing dispersion-strengthened materials with both high strength and ductility.
高温稳定性和机械性能是难熔钼合金在广泛的关键应用中所需要的特性。然而,这些合金长期存在的问题是它们延展性低,可成形性有限。在这里,我们报告了一种纳米结构化策略,实现了室温下屈服强度超过 800 MPa 且拉伸伸长率高达~40%的 Mo 合金。该加工路线涉及分子级别的液-液混合/掺杂技术,导致亚微米晶粒的最佳微观结构,纳米级氧化物颗粒均匀分布在晶粒内部。我们的方法可以很容易地应用于韧性 Mo 合金的大规模工业生产,可以在低温下进行广泛的加工和成型。这种多组分合金所采用的结构为制造高强度和高延展性的弥散强化材料提供了一种通用途径。