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101.
JIANG Zhouhua MA Jianghua ZHAN Dongping HE Jicheng YU Jin School of Materials & Metallurgy Northeastern University Shenyang China 《Baosteel Technical Research》2010,(Z1):21
In order to understand the effects of titanium,zirconium and magnesium on inclusions and the impact toughness of heat affected zone(HAZ) of steel,four low carbon steels deoxidized by titanium,zirconium and magnesium were obtained.After melting,forging,rolling and welding simulation,the inclusion characteristics (size,distribution,morphology and chemistry) analysis,Charpy-type test and the fracture observation of the specimens after the Charpy-type test were carried out respectively.The following results were found.A linear relationship exists between inclusions density and Ti content when Ti content ranges from 0.004%to 0.032% without Mg,and the proportion of inclusions in diameter less than 0.5μm decreases with the increasing of Ti content in steel.The density of inclusion increases rapidly when adding Ti-Zr-Mg deoxidant.The addition of Ti-Zr-Mg can enhance the impact toughness of HAZ after welding simulation.The maximal impacting energy after welding simulation is 249 J at 253 K.The complex particles of MgO-ZrO2-TiOx-MnS are most benefit to enhance impact toughness. 相似文献
102.
《Materials Science & Technology》2013,29(3):351-360
AbstractHeat affected zone (HAZ) microfissuring was investigated in electron beam welds of two Allvac 718 PLUS (718 Plus) alloys with different boron and phosphorus contents. Two preweld solution heat treatments were used and microfissuring susceptibility was evaluated by measuring the HAZ crack lengths in both alloys after bead on plate welding. The segregation behaviour of boron and phosphorus was studied before and after welding by secondary ion mass spectrometry (SIMS). Hot ductility behaviour of the alloys in the standard solution preweld heat treatment was also examined. The results of crack measurements, segregation studies and hot ductility tests correlated well with each other. It was observed that besides constitutional liquation of Nb rich MC type carbides, segregation of B and P largely influenced the microfissuring susceptibility of the alloy. Heat affected zone microfissuring increased with an increase in B + P concentrations and with an increase in the preweld solution heat treatment temperature. Segregation behaviour of B and P and its contribution to microfissuring in Allvac 718 Plus alloy were discussed. 相似文献
103.
Ma Chengyong Tian Zhiling Peng Yun Zhang Xiaomu He Changhong China Central Iron Steel Research Institute Beijing . Du Zeyu Tianjin University Tianjin . 《中国焊接》2005,(1)
0Introduction Intheprojectof“NewGenerationSteelMaterials”, oneoftheeffectiveapproachestoachieve800MPagrade steelsistoadoptRPCphasetransformationtechnique[1]. Atpresent,12 millimeter thickplatesteelwithyield strengthover800MPahasbeenobtainedbymeansofthis… 相似文献
104.
In order to predict the propensity of a superalloy to heat-affected-zone (HAZ) liquation cracking, Visual FORTRAN procedures
were developed based on a heat transfer and mass diffusion model and the constitutional liquation of precipitate (NbC) at
grain boundaries was simulated numerically. The results show that with the increase in the rate of welding thermal cycle,
the solid dissolution of precipitate prior to liquation decreases and the thickness of liquid film produced by constitutional
liquation increases. Higher heating rate inhibits the further melting of adjacent matrix and the solidification of liquid
by liquid-to-γ mode in the subsequent thermal cycle. As a result, the residual liquid film still maintains a great thickness
at the moment when temperature is down to the eutectic point, which will promote HAZ micro-fissuring. Finally, hot ductility
tests on a low-expansion superalloy were performed to verify indirectly the conclusions drawn from the numerical simulation. 相似文献
105.
Bum?Joon?Kim Seog?Hyeon?Ryu Byeong?Soo?LimEmail author 《Metals and Materials International》2004,10(1):19-25
In this study, the effect of microstructure on fatigue crack growth behavior of HAZ was investigated using newly developed
P92 steel weldment. Fatigue crack growth rates of the fusion line and fusion line+2 mm in HAZ were found to be faster than
that of welds or base metal, while fatigue crack growth rate of the fusion line+1 mm was the slowest. The fracture appearance
of the fusion line and fusion line+2 mm revealed mainly transgranular, cleavage-like faceted fracture surfaces and the fusion
line+1 mm showed quasi-cleavage fractures with scattered dimples, which increased resistance to fatigue crack growth. 相似文献
106.
中心偏析对连铸钢及其HAZ冲击性能的影响 总被引:1,自引:0,他引:1
研究了中心偏析对连铸10CrNi3MoV钢钢板及其焊接接头HAZ表面和心部冲击性能的影响,试验结果表明,中心偏析恶化了中心位置钢板及其HAZ的冲击性能;板厚中心位置试样的冲击功相对于表面位置的有一定下降,下降幅度随试验温度的降低有增大趋势。 相似文献
107.
讨论了以形变诱导相变为主的超细晶粒钢在添加合金元素铌以后热影响区组织性能的变化.试验结果表明:添加少量铌以后,粗晶区的韧性有所改善,但不能阻止母材晶粒的长大,韧性的下降不可避免,在实际焊接时,应避免过小的焊接热输入. 相似文献
108.
109.
110.
1 IntroductionHigh chromiumferritic heat resistant steels ,usually referred to the Cr-Mo steels ,are widely used inhigh temperature environment ,combining high strength at both ambient and elevated temperatures withadequate toughness[1].Based on basic crystal structure of materials ,the heat resisting steelsinclude perlit-ic ,bainitic and martensitic types . These steels contain chromiumcontents up to 12 % with usually about1 % Mo . They were usedin oil and processingindustry as early as 193… 相似文献