ABSTRACTs

The need for fully dense material with well-engineered microstructures has led to the promising emergence of innovative sintering technologies among which the Spark Plasma Sintering (SPS) is one of the most favorite. Unlike the conventional sintering processes, SPS takes advantage of a current flow passing through the sintering die and metallic powders by which fast densification with minimal grain growth and enhanced physicomechanical properties can be obtained. Albeit there is a growing interest in the exploitation of SPS in producing sufficiently consolidated metallic parts, no analytical review has been released over the effects of SPS parameters on the densification behavior, microstructure evolution, and resultant physicomechanical properties of metallic parts and their alloys. In the present review, recent developments and ongoing challenges in modeling the SPS of metallic systems are thoroughly explored. Then, the effects of main SPS parameters including sintering temperature, dwell time, heating rate, and pressure on the microstructure and physicomechanical properties of metals and alloys are comprehensively investigated. These properties are categorized into two groups: (i) physical properties including relative density, electrical and thermal conductivities; (ii) mechanical properties with a systematic focus on hardness, elastic modulus, and tensile, compressive, and bending strengths. In each section, the general trends along which SPS parameters grow to affect each corresponding property are comprehensively discussed. Additionally, various microstructural phenomena being more likely to occur at the given metallic systems are fully addressed. The present work seeks to elaborate on the aforementioned issues and provide an overview of the unresolved challenges and proposed solutions to them.

文摘

对具有精心设计的微结构的完全致密材料的需求导致了创新烧结技术的出现，其中火花等离子烧结 (SPS) 是最受欢迎的技术之一。与传统的烧结工艺不同，SPS 利用电流流过烧结模具和金属粉末，从而获得快速致密化、最小晶粒生长和增强的物理机械性能。尽管人们对利用 SPS 生产充分固结的金属部件越来越感兴趣，但还没有关于 SPS 参数对致密化行为、微观结构演变以及金属部件及其合金的物理机械性能的影响的分析评论。在本次审查中，对金属系统 SPS 建模的最新发展和持续挑战进行了深入探讨。然后，综合研究了烧结温度、保压时间、加热速率和压力等主要 SPS 参数对金属和合金微观结构和物理机械性能的影响。这些特性分为两组：(i) 物理特性，包括相对密度、电导率和热导率；(ii) 机械性能，系统地关注硬度、弹性模量以及拉伸、压缩和弯曲强度。在每个部分中，综合讨论了 SPS 参数增长以影响每个相应属性的一般趋势。此外，完全解决了在给定金属系统中更可能发生的各种微观结构现象。目前的工作旨在详细说明上述问题，并概述未解决的挑战和提出的解决方案。