W-Ni-Cu合金微观结构与力学性能研究进展

石海城, 王强松, 蔡廷军, 陈天宇, 贺瑜, 曹书光

精密成形工程 ›› 2026, Vol. 18 ›› Issue (2) : 31-47.

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精密成形工程 ›› 2026, Vol. 18 ›› Issue (2) : 31-47. DOI: 10.3969/j.issn.1674-6457.2026.02.004
兵器工艺技术

W-Ni-Cu合金微观结构与力学性能研究进展

  • 石海城1, 王强松2, 蔡廷军1,*, 陈天宇3, 贺瑜2, 曹书光2
作者信息 +

Recent Progress on Microstructure and Mechanical Properties of W-Ni-Cu Alloys

  • SHI Haicheng1, WANG Qiangsong2, CAI Tingjun1,*, CHEN Tianyu3, HE Yu2, CAO Shuguang2
Author information +
文章历史 +

摘要

W-Ni-Cu合金因其高密度、无磁性、优良的导电导热性能以及可调控的热膨胀系数,在对磁场敏感的精密仪器和高功率电器部件中表现出显著的应用潜力。传统W-Ni-Cu合金普遍存在强塑性匹配不佳的问题,严重限制了其工程应用范围。本文以该合金为研究对象,旨在揭示其微观组织与力学性能之间的内在关联,为突破现有性能瓶颈提供理论依据,系统梳理了近年来W-Ni-Cu合金在微观组织调控与力学性能优化方面的研究进展,重点分析了成分设计(如Ni/Cu比例优化)、合金化元素(如Fe、Co、La2O3等元素的添加)以及先进制备工艺(包括微波烧结、放电等离子烧结、热压烧结、选区激光熔化等)对合金微观结构、致密化行为及综合性能的影响规律。研究表明,通过调控Ni/Cu比例可有效改善合金的强塑性匹配;微量Co或La2O3的引入能够产生弥散强化与界面优化作用,显著提高合金的硬度与耐磨性;Fe元素的添加有效抑制了W颗粒的粗化并增强了W-W界面结合连续性,进而提升了合金的压缩与弯曲强度。在制备工艺方面,放电等离子烧结与热等静压技术促进了合金的快速致密化并抑制了晶粒粗化;选区激光熔化技术为复杂构件成形提供了新途径,但仍面临孔隙率控制与性能各向异性等挑战。此外,形变强化与热处理工艺(如淬火诱导γ相调幅分解)进一步优化了合金界面结构,实现了强度、塑性与低温韧性的协同提升。通过调控Ni/Cu比例、引入固溶元素以及优化多步烧结工艺,有效细化了W晶粒尺寸并改善了界面结合状态,从而协同提升了W-Ni-Cu合金的强度与塑性,为其在高端技术领域的应用提供了重要支撑。最后,对未来研究方向进行了展望,以期为开发高比重高强韧W-Ni-Cu合金提供理论依据与技术参考。

Abstract

W-Ni-Cu alloys demonstrate significant application potential in magnetic field-sensitive precision instruments and high-power electrical components due to their high density, non-magnetic properties, excellent electrical and thermal conductivity, and tunable thermal expansion coefficient. Traditional W-Ni-Cu alloys commonly suffer from a poor strength-ductility match which severely limits their engineering applicability. To address this issue, this study focuses on these alloys, aiming to elucidate the intrinsic relationship between their microstructure and mechanical properties, thereby providing a theoretical basis for overcoming this performance bottleneck. A systematic review was conducted on recent advances in the microstructural regulation and mechanical property optimization of W-Ni-Cu alloys with the emphasis placed on analyzing the effects of composition design (e.g., Ni/Cu ratio optimization), alloying elements (e.g., addition of Fe, Co, La2O3), and advanced preparation techniques (including microwave sintering, spark plasma sintering, hot pressing sintering and selective laser melting) on the alloys' microstructure, densification behavior, and comprehensive properties. Research showed that adjusting the Ni/Cu ratio effectively improved the strength-ductility balance of the alloys. The introduction of trace Co or La2O3 could induce dispersion strengthening and interface optimization, significantly enhancing hardness and wear resistance. The addition of Fe effectively inhibited the coarsening of W particles and enhanced the continuity of W-W interfaces, thereby improving the compressive and bending strengths of the alloys. In terms of preparation techniques, spark plasma sintering and hot isostatic pressing promoted rapid densification while suppressing grain coarsening. Selective laser melting provided a new approach for forming complex components, though challenges such as porosity control and property anisotropy remained. Furthermore, deformation strengthening and heat treatment processes (e.g., quenching-induced spinodal decomposition of the γ phase) further optimized the interfacial structure of the alloy, achieving simultaneous improvements in strength, plasticity, and low-temperature toughness. By optimizing the Ni/Cu ratio, introducing alloying elements, and refining multi-step sintering processes, the grain size of W could be effectively refined and the interfacial bonding state improved, thereby synergistically enhancing the strength and ductility of W-Ni-Cu alloys. This provides critical support for their application in high-end technological fields. Finally, this study outlines future research directions, aiming to offer theoretical insights and technical references for developing high-specific-gravity, high-strength, and high-toughness W-Ni-Cu alloys

关键词

W-Ni-Cu合金 / 高比重合金 / 粉末冶金 / 力学性能 / 微观结构调控

Key words

W-Ni-Cu alloy / high density alloy / powder metallurgy / mechanical properties / microstructure regulation

引用本文

导出引用
石海城, 王强松, 蔡廷军, 陈天宇, 贺瑜, 曹书光. W-Ni-Cu合金微观结构与力学性能研究进展[J]. 精密成形工程. 2026, 18(2): 31-47 https://doi.org/10.3969/j.issn.1674-6457.2026.02.004
SHI Haicheng, WANG Qiangsong, CAI Tingjun, CHEN Tianyu, HE Yu, CAO Shuguang. Recent Progress on Microstructure and Mechanical Properties of W-Ni-Cu Alloys[J]. Journal of Netshape Forming Engineering. 2026, 18(2): 31-47 https://doi.org/10.3969/j.issn.1674-6457.2026.02.004
中图分类号: TG146.4   

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河南省科技研发计划联合基金(245200810003)

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