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EB-PVD沉积Ni-Cr-Al合金的组织和力学性能的研究 赫晓东1,孙晔1,李垚1,关春龙1 (1.哈尔滨工业大学,复合材料研究所,哈尔滨,150001) 摘要:利用电子束物理气相沉积(EB-PVD)方法制备出厚度为0.5 mm的Ni-Cr-Al高温合金.研究了该合金在制备状态和长期时效后的显微组织及其力学性能.结果表明,制备态合金表面的晶粒尺寸约为185nm,并且材料断面呈层状结构.合金在760℃下时效16h,72h和120h后,材料断面的层状结构消失,且明显看到晶粒的存在.合金时效16h后,在靠近基板一侧形成柱状晶,但远离基板一侧为等轴晶.760℃长时间时效形成的主要强化相为γ''相.断口结果表明,制备态合金室温断口为混合型断口,接近基板一侧发生沿柱状晶边界的脆性断裂,而在另一侧为韧窝为主的韧性断裂.材料经长时间的真空时效后,断口由脆性断口转变为韧性断口.合金的室温显微硬度随......
to a large extend. Key words: Ni-Cr-Al based alloy; hot corrosion; Cr content; preoxidation; kinetics; corrosion mechanism 1 Introduction Ni-Cr-Al based alloy is a widely used superalloy which offers...-Cr, Fe-Al. NIU et al [2] studied the hot corrosion behavior of Ni-Al intermetallic compound in the combustion gas at 600-800 °C and proved that the appearance of sulfides accelerated the hot corrosion......
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precipitates forms on Ni-10Al, while Ni-5Cr-10Al develops a protective layer. So the addition of Cr promotes the formation of alumina scale. The possible mechanism of Cr on the oxidation of Ni-Al alloy is discussed. Key words: Ni-Cr-Al alloy; Ni-10Al alloy; oxidation; third-element effect 1 Introduction Binary and ternary Ni-based alloys are often used as model systems to study the processes occurring......
Microscopic phase-field simulation coupled with elastic strain energy for precipitation process of Ni-Cr-Al alloys with low Al content LU Yan-li(卢艳丽), CHEN Zheng(陈 铮), LI Yong-sheng(李永胜), WANG...; Abstract: The precipitation process of Ni-Cr-Al alloy with low Al content was studied at atomic scale based on the microscopic phase-field kinetic model coupled with elastic strain energy. The aim......
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coating system combining an arc-ion plating technique and a DC reactive magnetron sputtering technique using Cr and Al targets in the Ar/N2/CH4 gaseous mixture. The effect of carbon content... coatings by a hybrid coating system [J]. Surface and Coatings Technology, 2006, 201: 4068-4072. [9] TAM P L, ZHOU Z F, SHUM P W, LI W Y. Structural, mechanical, and tribological studies of Cr-Ti-Al-N......
温度对Ni-Cr-Al合金中Cr原子替代规律的影响褚忠1,2,赵国群1,陈铮31. 山东大学2. 青岛理工大学3. 西北工业大学凝固技术国家重点实验室摘 要:利用微观相场动力学模型,模拟研究温度对Ni-12at%Cr-14.5at%Al合金沉淀过程中Cr原子的替代规律.在873~1173K范围内,随着温度的提高,合金沉淀机制由等成分有序化+失稳分解转化为非经典形核机制,沉淀孕育期逐渐延长;L12相体积分数增加,而D022相体积分数减少,在1173K时,D022相消失,最终形成单一的L12相.关键词:Ni-Cr-Al;替代;模拟;微观相场模型;......