【摘 要】
：
The oxidation behavior of welded HastelloyXsuperalloy, containing the substrate(X-SUB),heat-affected zone (X-HAZ) and the melt zone (X-MZ) and as-cast FeCoNiCrAl high-entropy alloy (H5-HEA)was studied
【机 构】
：
Institute of Materials Engineering, National Taiwan Ocean University, Keelung 202, Taiwan
【出 处】
：
The 4th International Symposium on Materials and Reliability
论文部分内容阅读
The oxidation behavior of welded HastelloyXsuperalloy, containing the substrate(X-SUB),heat-affected zone (X-HAZ) and the melt zone (X-MZ) and as-cast FeCoNiCrAl high-entropy alloy (H5-HEA)was studied at 950℃ in dry air.The oxidation kinetics of the two alloys followed the parabolic rate law.The steady-state oxidation rate constants (kpvalues) were calculated based on the mass-gaindata, and the oxidation resistant ability of the alloys followed by the rank of H5-HEA> X-SUB>X-MZ>X-HAZ.An exclusive thin-layer of-and-Al2O3 was grown on the H5-HEA alloy, while duplex scales formed on all the X alloys consisted of a heterophasic mixture of Cr2O3 and MnCr2O4.The detail oxidation mechanisms for the two alloys were systematically investigated.
其他文献
采用净浆流动度、TOC吸附、红外光谱等试验,研究循环流化床灰对聚羧酸盐减水剂吸附性能的影响,探讨其影响聚羧酸减水剂分散性能的机理,并提出加入无机盐以此改变硫酸根离子及氧化铁的含量来提高循环流化床灰与聚羧酸盐减水剂之间的适应性.研究结果表明:循环硫化床灰中氧化铁、硫酸根离子等都存在着与聚羧酸减水剂吸附的可能,使浆体的流动性大大降低;当循环流化床灰中Na2SO4的含量达3％时,浆体基本失去流动性,随循
利用红外光谱仪表征了一种聚羧酸减水剂,研究了聚羧酸减水剂在水泥水化中的作用;水泥颗粒吸附聚羧酸减水剂后粒径先减小后增大,Zeta电位分析表明聚羧酸减水剂利用空间位阻对水泥进行分散,水泥水化3天龄期XKD衍射有AFt存在,表明聚羧酸减水剂有延缓水泥水化作用,与水泥水化产物热分析结论一致;聚羧酸减水剂对水泥分散作用较好;可延缓水泥水化反应.
探讨了聚羧酸减水剂分子结构与早强性的关系,并从聚羧酸减水剂的种类、主侧链长度及密度、功能性单体等角度出发,探究了聚羧酸减水剂早强性影响因素.介绍了早强性的表征方法.指出了早强型聚羧酸减水剂研究和生产中存在的问题,并对其未来的发展提出了展望.
近年来，伴随着聚羧酸减水剂的快速发展，现代水泥混凝土技术也得到了快速的发展，其中变现尤为明显的是辅助性胶凝材料在混凝土中的应用日益广泛，且种类繁多，掺量越来越大。随之而来的由于混凝土拌合物中的各类原材料的相容性引起的混凝土早期工作性的问题逐渐突显，特别是各种胶凝组分和外加剂之间的相容性。聚羧酸减水剂不同分子结构对其在混凝土各胶凝材料表面的吸附有较为显著的影响，这些研究有利于指导科研工作者针对不同需
Chemical composition analysis, microstructure analysis, macro and micro fracture morphology analysis were conducted on a cracked leak off tube in primary heat transport and heavy water collection syst
Welded 304L stainless steel is the weak link in pressurized water reactor (PWR) components, Stress corrosion cracking (SCC) of simulated reactor components welded 304L stainless steel in 5mg/L chlorid
采用直流电压降测量裂纹长度的方法,研究了316LN不锈钢管道在不同的一回路水化学条件下的疲劳和应力腐蚀开裂规律.实验结果发现,316LN的疲劳裂纹扩展速率随载荷比和频率的降低而下降,不同的水化学条件下,材料的应力腐蚀裂纹扩展速率受溶解氧影响显著.在通入2ppm氧气的条件下,材料在含B-Li水中的裂纹扩展速率最高,而在含氢水中材料裂纹扩展速率受水中溶质的影响很小.
Austenitic stainless steel 316L has been well used as one of the structural materials of components in the nuclear reactor.However, severe SCC phenomenon has been found during the service.It is sugges
A 3-D sequential coupling finite element simulation is performed to investigate thetemperature field and residual stress in the dissimilar metal weld of a PWR safe-end and nozzle.Chemical compositions
目前国内外新建压水堆核电厂中,反应堆压力容器接管与主管道安全端之间主要采用52合金焊材焊接,经工厂焊接后成为可实际应用于核电厂的焊接件.国外实验室研究结果表明,国外52合金异种金属焊接(52Mw)材料在模拟压水堆一回路高温水环境中出现应力腐蚀裂纹扩展,裂纹扩展速率比82/182合金异种金属焊接材料低2个数量级.本文对国产52Mw合金异种金属焊接材料应力腐蚀裂纹扩展行为进行了试验研究.结果表明,国产