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1.
选择含氮节镍型QN2109Mo奥氏体不锈钢作为研究对象,采用XRD、TEM、SEM、EDS、摩擦磨损试验机和电化学工作站等检测手段,研究QN2109Mo不锈钢的组织结构、摩擦磨损性能以及耐腐蚀性能,并与316L不锈钢进行对比。实验结果表明:N原子主要以间隙固溶形式存在于QN2109Mo不锈钢中,对QN2109Mo不锈钢组织起到了细化作用,提高了QN2109Mo 不锈钢的硬度。在干摩擦状态下,QN2109Mo不锈钢的耐磨损性能优于316L不锈钢,其磨损机理为氧化磨损和磨粒磨损共同作用。在w(NaCl)为3.5%的溶液中,QN2109Mo不锈钢表现出比316L不锈钢更低的自腐蚀电流密度和更高的点蚀电位,具有更优异的耐NaCl 溶液腐蚀性能。  相似文献   

2.
根据高炉炉壳生产实际,分别使用气电立焊和埋弧自动横焊两种焊接工艺对50 mm厚的BB503型炉壳用钢板进行焊接,对焊缝进行外观检查、无损探伤,对焊接接头进行拉伸、侧弯、冲击、硬度等性能测试,并对焊接热影响区的显微组织进行了观察和分析。结果表明,BB503炉壳用钢的气电立焊和埋弧自动横焊焊接接头抗拉强度和冲击吸收功均大于母材,具有优良的综合力学性能;焊缝区及热影响区的显微维氏硬度分布和热影响区的组织均匀性均显著优于传统的CO2气体保护焊和手工电弧焊接头。气电立焊和埋弧自动横焊工艺可以替代CO2气体保护焊和手工电弧焊工艺用于高炉炉壳焊接制造。  相似文献   

3.
双相不锈钢容器焊接的主要问题不在焊缝,而在热影响区.因为在焊接热循环作用下,热影响区处于快冷非平衡态,冷却后总是保留更多的铁素体,从而增大了腐蚀倾向和氢致裂纹(脆化)的敏感性.本文分析了双相不锈钢容器的焊接特点和焊接时常出现的问题,提出了焊接双相不锈钢容器的方法及工艺.  相似文献   

4.
对40Mn18Cr4V无磁钢进行了三种不同工艺的激光对接焊,分析不同焊接工艺条件下激光焊接头的金相组织和显微硬度。结果表明焊缝金属中有大量δ铁素体形成,焊缝和热影响区的显微硬度较母材均降低,说明该钢种不适合于激光对接焊,只有使用激光填丝复合焊才有可能满足40Mn18Cr4V钢的焊接技术要求,同时所使用的焊丝成分也不能与母材成分完全相同。  相似文献   

5.
采用有限元方法,建立了激光焊接不锈钢的三维瞬态温度场的计算模型,考虑了材料的热物理性能、相变潜热与温度的非线性关系以及表面对流换热和辐射散热等影响因素,使用SYSWELD软件对激光焊接过程中的温度场进行了分析。结果表明:在激光焊接的开始阶段和结束阶段温度快速上升,中间阶段温度变化较缓慢;沿激光束扫描方向和与扫描方向垂直的方向都存在较大的温度梯度,温度梯度的存在引起较大的热应力,而热应力的存在是焊接过程中易产生裂纹的主要原因。  相似文献   

6.
唐威 《唐山学院学报》2021,34(3):10-14,28
采用激光填丝焊对Al-Li-Er铝合金进行焊接处理,研究激光功率、焊接速度和送丝速度对焊接接头显微组织与力学性能的影响。结果表明,当送丝速度为3 m/min和4 m/min时,Al-Li-Er合金焊接接头的焊缝面积都会随着激光功率和焊接速度的增大而逐渐减小;在相同激光功率和焊接速度时,送丝速度的增加会增大焊缝面积,且随着送丝速度的增加,激光焊接接头的上余高系数和下余高系数都呈现逐渐增加的趋势。Al-Li-Er合金适宜的激光焊接工艺参数为激光功率3 kW、焊接速度3 m/min、送丝速度2~3 m/min,此时焊接接头的室温拉伸性能与母材较为接近。  相似文献   

7.
进行了29mm规格铁路车辆用GR65钢焊接性能研究,结果表明:GR65钢具有优良的抗裂性能,热影响区淬硬倾向较小。匹配WER60焊丝采用富氩气体保护焊接,焊缝组织为针状铁素体+少量的晶内先共析铁素体,焊接接头强度605MPa,焊缝-40℃冲击功达到171J,远高于技术条件要求。  相似文献   

8.
Micro-plasma arc surface melting of 0Cr19Ni9 shielded metal arc welding joint with a micro-plasma arc welder produced a thin surface melted layer with a refined microstructure. The surface treatment changed the anodic polarization behavior in 0.5 mol/L H2SO4 solution. The polarization tests showed that for the as-welded joint both the heat-affected zone and the weld metal decreased in resistance to corrosion compared with the as-Received parent material while for the micro-plasma arc surface melted joint the corrosion resistance increased significantly. This increase in corrosion resistance is attributed to the rapid solidification of the melted layer. Rapid solidification of the melted layer refines its microstructure, decreases its microsegregation, and inhibits the precipitation of chromium carbides at the grain boundaries.received parent material while for the micro-plasma arc surface melted joint the corrosion resistance increased significantly. This increase in corrosion resistance is attributed to the rapid solidification of the melted layer. Rapid solidification of the melted layer refines its microstructure, decreases its microsegregation, and inhibits the precipitation of chromium carbides at the grain boundaries.  相似文献   

9.
某医院植入患者体内的不锈钢接骨板和骨钉发生失效断裂。采用化学分析、断口和金相观察对该断裂失效的原因进行了分析。结果表明:00Cr18Ni15Mo3N接骨板孔洞边缘存在疏松孔隙和微裂纹是导致其断裂的主要原因;00Cr18Ni14Mo3骨钉断裂与其棱边小侧面存在的毛刺相关,同时其组织中异常存在的铁素体也加速了骨钉的断裂。  相似文献   

10.
本文研究用激光表面处理使碳素钢表面合金化,从而提高普通碳素钢的耐蚀性,且研究表明随着焊缝中铬含量的增加,耐蚀性提高。研究还表明用较高的扫描速度和较大的激光功率可获得稳定的焊逢形状。  相似文献   

11.
采用搅拌摩擦焊技术对6061-T5铝合金进行焊接,分析了焊接速度对接头成形、微观结构及力学性能的影响.结果表明:随着焊接速度的增加,沉淀相固溶度下降,晶粒细化;焊接速度过大时,热输入不足,呈现原始态组织.当转速为800 r/min,焊接速度为60 mm/min时,接头成形良好,抗拉强度达到最大值.采用合适的搅拌摩擦焊工艺参数,6061-T5铝合金能实现可靠的连接.  相似文献   

12.
By using semisolid joining technique,the bonding of stainless steel and semisolid aluminum alloy is successfully realized.The relationships between interracial shear strength and solid fraction of aluminum alloy,bonding pressure and time of keeping pressure were studied by the method of orthogonal experiment.The interfacial structure and the fracture structure of the bonding plate are studied by means of optical microscope (OM) and scanning electron microscope (SEM).The results show that there is the best solid fraction between the solid phase line and the liquid phase line of the semisolid aluminum alloy,with the increase of bonding pressure and pressure time,the interfacial shear strength increases rapidly,and then with further increase of bonding pressure and pressure time,the shear strength rises little.Along the interface,solid phase and liquid phase bond with stainless steel by turns because of the different diffusion ability.So,a new type of non-equilibrium diffusion interfacial structure is constructed at the interface of stainless steel and aluminum alloy,compound mechanism of plastic and brittle fracture interface was formed at the shear fracture interface.  相似文献   

13.
试验研究了热处理对CuCr/1Cr18Ni9Ti双金属复合材料结合区组织和性能的影响。结果表明,热处理后,结合区没有明显的裂纹和脆化现象,界面反应层宽度无明显增加;热处理工艺明显提高了1Cr18Ni9Ti奥氏体不锈钢的硬度,界面反应层和CuCr合金的显微硬度略有增加。  相似文献   

14.
不锈钢复合钢板是一种由基层和复层组成的双层金属钢板,在石油化工装置中使用十分广泛。针对不锈钢复合钢板的焊接性特点,从坡口的选择、焊接方法、焊接材料、错变量的控制、焊后热处理和无损检测等工艺因素入手,阐述和提出了适合不锈钢复合钢板在石油化工设备制造生产中的焊接工艺措施。实践证明,这些工艺方法与措施在实际生产中可借鉴使用,并具有良好的针对性和实用效果。  相似文献   

15.
奥氏体不锈钢构件的腐蚀机理与焊接方法   总被引:1,自引:0,他引:1  
基于奥氏体不锈钢材料越来越多的应用于不同的工业企业生产当中,为减少和避免加工过程中对材料原有优良性质改变,通过长期对其在船舶工业中的应用特点和工艺方法的实践研究,针对奥氏体不锈钢构件的抗腐蚀特性进行理论分析,揭示其工作在腐蚀环境中的抗腐蚀机理,并以焊接加工为例,指出不恰当的生产方法对奥氏体不锈钢的抗蚀特性的影响,提出了合理的工艺手段和改进措施。  相似文献   

16.
The eff ect of Zn interlayer on the microstructural evolution and mechanical behavior of dissimilar ultrasonic-spot-welded Al/Cu joints was investigated. The tensile lap shear strength in relation to welding energy was analyzed. The experimental results show that two intermetallic compounds, Cu_5Zn_8 and Al_2Cu, were generated at the interface of the ultrasonic-spotwelded Al/Cu joint with a Zn interlayer. The primary joining mechanisms of the joint included the intermetallic compound bonding and metallic bonding caused by solid shear plastic deformation. Meanwhile, with increasing welding energy, the plastic deformation of the material became more substantial. With increasing welding energy, the tensile lap shear strength of the joints fi rst increased and then decreased for the ultrasonic-spot-welded Al/Cu joints with and without Zn interlayers. Under the energy input of 700 J, the bearing load capacity of the ultrasonic-spot-welded Al/Cu joints with a Zn interlayer improved signifi cantly due to the observed intermetallic compound(Cu_5Zn_8).  相似文献   

17.
Pinless Friction Stir Welding of AA2024-T3 Joint and Its Failure Modes   总被引:1,自引:0,他引:1  
The joining of aluminum alloy sheets with thickness less than 2.0 mm is difficult via conventional frictionstir welding owing to the defects in the joint, such as root flaw, keyhole and lazy S. In the present research, a newlydesigned pinless tool with involute grooves on its shoulder surface was applied to weld 1.5 mm thick AA2024-T3. Theeffects of the rotating speed and welding speed on the microstructure and mechanical properties of the joints were analyzed.The experimental results showed that the root flaw and keyhole were successfully eliminated. The lazy S wasalso eliminated under the optimized welding parameters. The maximum tensile strength of the joints was 326 MPa,which is about 74.1% that of the base material. Moreover, all the tensile samples fractured from the retreating side.Two fracture modes were observed during the tensile tests, which are related with the lazy S.  相似文献   

18.
基于仿真模拟软件SYSWELD,建立了P91钢材料属性数据库,设计开发了考虑马氏体相变的“热-冶金-力学”耦合计算方法,采用热循环曲线法对P91钢平板对接接头残余应力场进行数值模拟仿真分析。参照原始焊接工艺方案进行上下0.5mm/s焊接速度的调整,并进行残余应力仿真计算。结果表明,马氏体相变能抵消焊缝热收缩时产生的拉应力。后道焊缝焊接过程中施加的热载荷对前道焊缝应力变化和平板角变形有着显著的影响。考虑后道焊缝焊接过程中施加的热载荷对前道焊缝组织变化的影响时,焊接接头整体的拉应力大幅度下降,热影响区的拉应力上升,角变形起缓和作用。焊接速度越大,Von Mises残余应力和横向残余应力越大,纵向残余压应力越小。  相似文献   

19.
通过研究YAG激光器谐振腔腔长与光束质量的关系,优化设计谐振腔腔长,得到了良好的激光光束质量。当激光器腔长L=766mm时,激光的光束质量最好,高斯分布均匀,对薄板不锈钢进行穿透焊接工艺试验,此腔长的焊接效果最好。  相似文献   

20.
18—8型奥氏体不锈钢焊接工艺研究   总被引:1,自引:0,他引:1  
从焊前准备、焊接材料选用、防变形措施、焊接规范、操作标准、前期预热及焊后热处理等方面探讨18—8型奥氏体不锈钢的焊接工艺,具有一定的推广价值。  相似文献   

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