1000℃下热处理时间对内燃机用颗粒增强镍基合金组织和硬度的影响  

Effect of Heat Treatment Time on the Microstructure and Hardness of Particle Reinforced Ni-Base Alloy for Internal Combustion Engine under 1000℃

作　　者：陈晓静 屈建华 董彬[3] CHEN Xiao-jing;QU Jian-hua;DONG Bin(College of Automotive Engineering,Yellow River Institute of Communications,Zhengzhou 450000,China;School of Mechanical Engineering,Henan University of Technology,Zhengzhou 450000,China;School of Transportation,Yellow River University of Science and Technology,Zhengzhou 450000,China)

机构地区：[1]黄河交通学院汽车工程学院,河南郑州450000 [2]河南工业大学机械工程学院,河南郑州450000 [3]黄河科技学院交通学院,河南郑州450000

出　　处：《材料保护》2021年第8期75-78,84,共5页Materials Protection

基　　金：河南省高等学校重点科研项目(18B410002)资助。

摘　　要：为了提高内燃机用镍基合金的组织性能,选择镍基粉末合金作为测试材料,先利用热挤压固结成型方法获得具有致密组织结构的棒材,再进行1000℃不同热处理时间的处理。通过试验测试的手段研究其微观组织和硬度。结果表明:热挤压态镍基合金晶粒大小均匀性较差,发生了小晶粒聚集现象。热挤压处理后的合金出现了大量的高密度位错,并且发生了相互堆积的情况。经过热挤压后镍基合金的力学强度得到明显的提升。热处理时间至8 h时,形成了更大的晶粒,但生长速率发生了减小。经过8 h热处理后,晶粒尺寸进一步变大,但速率发生了减缓,大部分纳米颗粒都分布于晶粒中和晶界区域,粒径约35 nm。逐渐延长热处理时间后,硬度发生了快速减小。热处理时间到8 h时,合金获得了稳定的硬度,经过96 h热处理后的试样硬度达到了最小。In order to improve the microstructure and properties of nickel-based alloy for internal combustion engine,with selecting nickel-based powder alloy as the test material,the bars with compact microstructure were obtained by hot extrusion consolidation molding method firstly,and then the bars were processed by the thermal treatment with different time under 1000℃.In addition,the microstructure and hardness were studied by means of experimental test.Results showed that the grain size uniformity of hot-pressed nickel-based alloy was poor,and the phenomenon of small grain aggregation occurred.After hot extrusion treatment,a large number of high-density dislocations and mutual accumulation appeared in the alloy,and the mechanical strength of nickel-base alloy was improved greatly after hot extrusion.When the heat treatment time reached 8 h,the size of grains continued to grow larger,but the rate of growth decreased.After 8 h of heat treatment,the grain size was further increased,but the rate was slowed down.Most of the nanoparticles were distributed in the grain and grain boundary area,with a particle size of about 36 nm.Furthermore,the hardness decreased rapidly under the condition of prolonging heat treatment time gradually.The alloy obtained stable hardness after 8 h heat treatment,while the hardness of the sample became the minimum after 96 h heat treatment.

关 键 词：镍基合金 颗粒强化 热处理 热挤压 微观组织 硬度 

分 类 号：TG156[金属学及工艺—热处理]