冷却速率对激光增材GH4099合金中显微组织及性能影响研究  

Role of Cooling Rate on Microstructure and Properties of Laser Additive Manufactured GH4099 Alloy

作　　者：潘维 王毅 扈圣军 张春来 韩翼龙 PAN Wei;WANG Yi;HU Shengjun;ZHANG Chunlai;HAN Yilong(Beijing Innogreen Technology Limited Corporation,Beijing 100068,China;Beijing Hangxing Machinery Manufacture Limited Corporation,Beijing 100013,China)

机构地区：[1]北京英诺格林科技有限公司,北京100068 [2]北京航星机器制造有限公司,北京100013

出　　处：《精密成形工程》2024年第10期107-114,共8页Journal of Netshape Forming Engineering

基　　金：装备预研共用技术(5092305XXXX)。

摘　　要：目的研究不同冷却速率下增材制造GH4099合金显微组织及相关力学性能的演化规律,通过调控合金在中高温温度区间内的停留时间优化合金弥散分布的第二相组织,进而提升合金硬度。方法分别利用高温热处理炉对合金进行固溶及后续冷却热处理;利用光学显微镜(OM)、扫描电子显微镜(SEM)和透射电子显微镜(TEM)等表征手段分析合金打印态和不同冷速热处理态显微组织的演变规律,重点分析冷却过程中形成的弥散分布的碳化物和强化相;利用维氏硬度计分析合金的显微硬度,并与其显微组织信息相对应。结果在打印态合金中,存在基于位错的亚结构,且并未发现弥散分布的强化相,其硬度相对较高。固溶水冷处理后,打印态亚结构消失,无弥散分布的碳化物或强化相,其硬度下降至200HV。固溶空冷合金中存在大量弥散分布的碳化物与强化相,但是由于其冷却速度相对较快,该类弥散分布第二相尺寸较小,其硬度提升幅度有限(300HV)。在固溶炉冷样品中存在大量弥散分布的碳化物和强化相,其硬度达到所有样品的最大值(400HV)。结论通过对比不同冷却速率下合金的组织与性能演变规律,明确了与合金强度相关的显微组织、弥散分布的第二相的调控机制,即延长了合金在中高温区间内的停留时间,经固溶炉冷后的GH4099合金硬度显著提升。The work aims to study the evolution of microstructure and related mechanical properties of the additive manufactured GH4099 alloy at different cooling rates,and optimize the second phase microstructure of the alloy dispersion distribution through time regulation in the medium and high temperature range,so as to improve the alloy hardness.High-temperature heat treatment furnaces were used to perform solid solution and subsequent cooling heat treatment on the alloy,and characterization techniques such as optical microscopy(OM),scanning electron microscopy(SEM),and transmission electron microscopy(TEM)were used to analyze the microstructural evolution of the alloy as printed and heat-treated at different cooling rates,with a focus on the dispersed carbides and strengthening phases formed during the cooling process.A Vickers hardness tester was used to analyze the microhardness of the alloy and correspond with the microstructure information.In the as-built alloy,there were dislocation-based substructures,with no dispersed strengthening phases,resulting in relatively high hardness.After solid solution and water-cooling treatment,the substructure in previous as-built sample disappeared without dispersed carbides or strengthening phases,and its hardness decreased to 200HV.There were a large number of dispersed carbides and strengthening phases in solid solution and air-cooled alloy,but due to their relatively fast cooling rate,the size of these dispersed second phases was small,resulting limited hardness improvement(300HV).There were a large number of dispersed carbides and strong interactions in the furnace-cooling samples after solid solution treatment,and their hardness reached the maximum value of all samples(400HV).By comparing the evolution of microstructure and properties of alloys under different cooling rates,the microstructure that affects the strength of the alloy,the dispersed distribution of the second phase and the control mechanism based on component segregation and diffusion are clarified.That is,by ext

关 键 词：镍基高温合金 增材制造 碳化物 强化相 组织性能 

分 类 号：TG146.15[一般工业技术—材料科学与工程]