沉淀硬化不锈钢真空电子束焊接工艺研究

介绍了15—5PH马氏体沉淀硬化不锈钢材料的特点和应用场合,着重论述了该材料的真空电子束焊接工艺试验。试件经X射线探伤显示焊缝质量满足国军标I级,焊接接头在室温下的力学性能指标均满足设计和使用要求,从而验证了15—5PH不锈钢材料具有优异的真空电子柬焊接性能。该工艺方法已成功应用于某产品天线座转台的研制。     

平台工艺管线用TP316L不锈钢焊接工艺研究

本文通过对TP316L不锈钢的焊接性进行分析,确定了采用的焊接方法、焊接材料及坡口形式等。通过焊接工艺试验,确定了该不锈钢的焊接工艺,最终获得了具有良好的力学性能和耐腐蚀性能的焊接接头。     

ZG0Cr25Ni7Mo2N低碳双相不锈钢补焊工艺的研究

针对ZG0Cr25Ni7Mo2N低碳双相不锈钢产品在生产中出现的焊接不稳定问题,经常出现返修补焊的现象,论文对ZG0Cr25Ni7Mo2N低碳双相不锈钢铸件补焊进行研究,使用焊条电弧焊的方法,选用2209-15低氢焊条,采用多层多道焊,通过确定合理的工艺参数及焊接方法,分析焊接接头的金相组织,对焊接接头力学性能进行检测,验证ZG0Cr25Ni7Mo2N低碳双相不锈钢在使用2209-15低氢焊条,采用所选焊接工艺条件下,焊接接头是否能满足产品要求。解决双相不锈钢铸件焊接产品在精加工出现缺陷。经过试验确定,焊接热影响区主要由双相组织组成,焊缝区域主要由奥氏体组织和少量铁素体组织组成,焊接接头力学性能满足使用要求.     

X6CrNiTi18-10焊后热处理的工艺研究

通过选择焊接材料、焊接方法、工艺参数及热处理规范等对X6CrNiTi18-10奥氏体不锈钢进行焊后热处理的工艺试验研究。通过常温力学性能,焊接接头的微观金相组织分析了焊缝的强度及组织状态。最终试验结果表明工艺方案可行,可指导实际生产。     

Inconel690与321不锈钢异种管材的焊接

通过Inconel690与321不锈钢异种管材的焊接工艺性试验,确定了异种金属焊缝的焊接材料以及合理的焊接工艺规范参数,并通过焊接接头力学性能试验结果表明,焊接的异种金属焊接接头各项力学性能,完全满足了核电产品设备规格书的要求,为300MW核反应堆压力壳产品的驱动管座的焊接奠定了坚实的基础。     

工业纯钛TA2焊接技术在钛液薄膜蒸发器中的应用

以工业纯钛TA2为主体材料的钛液薄膜蒸发器,其技术关键在于确定合适的焊接工艺保证焊接接头的焊接质量及各项力学性能指标,以适应钛液介质的腐蚀。为了摸索TA2钛焊接的特点及操作要领,进行了一系列焊接工艺试验,通过试验及分析确定出最佳的"断弧焊"焊接工艺规范参数,最后完成产品的焊接。     

Inconel690与321不锈钢异常管材的焊接

通过Inconel690与321不锈钢异种管材的焊接工艺性试验,确定了异种金属焊缝的焊接材料以及合理的焊接工艺规范参数,并通过焊接接头力学性能试验结果表明,焊接的异种金属焊接接头各项力学性能,完全满足了核电产品设备规格书的要求,为300MW核反应堆压力壳产品的驱动管座的焊接奠定了坚实的基础。     

阀门膨胀节用接管和波纹管焊接工艺的分析

介绍了阀门膨胀节中的接管和波纹管分别选用15Cr Mo和304不锈钢材料连接的焊接工艺。通过对15Cr Mo、304不锈钢及其异种接头焊接性分析,对比分别采用Ni基合金和奥氏体不锈钢填充材料时,获得的焊缝组织,结合焊接性分析结果,确定焊接工艺、制定焊接工艺参数。     

0Cr18Ni9不锈钢埋弧焊工艺

本公司从辽宁华锦集团乙烯改扩建工程中承接了一台脱甲烷预分离塔（T—1410）制造任务。由于操作介质苛刻,故设计上选用耐腐蚀的不锈钢材料0Cr18Ni9。对0Cr18Ni9不锈钢进行焊接性分析,从焊接方法、焊接材料、焊接参数等方面进行焊接工艺性试验,分析总结出了合适的焊接工艺,并成功应用于该设备的制造。     

不锈钢容器制造中的自动埋弧焊工艺优化探讨

本文结合生产实际,对自动埋弧焊技术应用在不锈钢容器制造过程中的焊接设备性能、焊接工艺因素、焊接材料及工艺参数选择、对比试验等进行综述。     

Strength and microstructure of laser fusion-welded Ti–SS dissimilar material pair

The ability to efficiently create robust and reliable dissimilar metal joints has the potential to enable new functionalities and reduce the manufacturing costs of medical devices. The need for dissimilar material welds in the medical device industry is driven by the unique properties exhibited by biocompatible materials such as stainless steel and titanium, as well as shape memory materials such as NiTi. Many material pairs, however, suffer from significant intermetallic phase formation during welding which greatly reduces their strength. This study investigates the microstructures and strength of the laser fusion-welded titanium–stainless steel dissimilar material pair as a simplified model of the NiTi–stainless steel pair. Compositional and structural analysis of the weld pool is performed and fracture morphologies are analyzed in different regions of the weld joint. The role of weld pool geometry, heat flow, and quench rate on the resultant phases, microstructures, and strength of the welds is discussed.     

Experimental investigation of the effect of vibration on mechanical properties of 304 stainless steel welded parts

Some of the problems that occur during the welding process include the creation of coarse grains in the weld structure and the hardening of the weld region, which reduce the strength and impact resistance of the welded parts. One technique to improve the mechanical properties of weld is the application of mechanical vibration to the molten pool. In this article, the effect of vibrating the part during welding on the mechanical properties of steel plates has been investigated in the tungsten inert gas (TIG) welding process. The plate is made of stainless steel 304 with 2 mm in thickness. A filler material has also been used for welding so that the effect of vibration can be observed on the weld pool region. The experimental tests have been performed under different welding conditions with respect to voltage, current, welding speed, vibrations amplitude, and frequency. Then, the resultant mechanical properties of the tested parts were measured. Also, the microstructure obtained by applying the vibration has been examined. Based on these experimental results, the effect of mechanical vibration on mechanical properties of the weld was investigated. Moreover, considering the mechanical properties obtained from these experiments, the optimum values of amplitude, frequency, and welding speed were determined.     

17—4PH马氏体沉淀硬化不锈钢阀座的试制

介绍了用17-4PH钢加工阀座的加工过程、热处理方法及其注意事项。通过实验及测量等方法分析了17—4PH钢作为阀座材质的可行性。     

热处理工艺对17-4PH不锈钢力学性能的影响

对17～4PH不锈钢进行四种不同工艺(固溶+时效)热处理,对热处理后该钢的显微组织、力学性能及冲击断口进行观察分析,研究了热处理工艺对17-4PH不锈钢力学性能的影响.结果表明:未经调整处理的三组试样,随着时效温度的升高,其强度下降,塑、韧性提高,冲击断口均为典型的准解理脆性断裂;经调整处理的一组试样,其强度较其他试样的要低,但塑、韧性与其他试样相比明显提高,冲击断口具有明显的韧性断裂特征;经调整处理后试样的马氏体组织较均匀细小.     

Determination of Elastoplastic Mechanical Properties of the Weld and Heat Affected Zone Metals in Tailor-Welded Blanks by Nanoindentation Test

The elastoplastic mechanical properties of the weld and heat affected zone metals have comparatively major impact on the forming process of tailor-welded blanks. A few scholars investigated the elastoplastic mechanical properties of the weld and heat affected zone, but they only simply assumed that it was a uniform distribution elastoplastic material different from the base materials. Four types of tailor-welded blanks which consist of ST12 and 304 stainless steel plates are selected as the research objects, the elastoplastic mechanical properties of the tailor-welded blanks weld and heat affected zone metals are obtained based on the nanoindentation tests, and the Erichsen cupping tests are conducted by combining numerical simulation with physical experiment. The nanoindentation tests results demonstrate that the elastoplastic mechanical properties of the weld and heat affected zone metals are not only different from the base materials, but also varying between the weld metals and the heat affected zone metals. Comparing the Erichsen cupping test resulted from numerical with that from experimental method, it is found that the numerical value of Erichsen cupping test which consider the elastoplastic mechanical properties of the weld and heat affected zone metals have a good agreement with the experimental result, and the relative error is only 4.8%. The proposed research provides good solutions for the inhomogeneous elastoplastic mechanical properties of the tailor-welded blanks weld and heat affected zone metals, and improves the control performance of tailor-welded blanks forming accuracy.     

A new thermal error modeling method for CNC machine tools

Shape memory superelastic alloys as NiTi have mechanical properties and biocompatibility characteristics quite interesting for a set of industries, amongst which is the medical industry. They find applications in tools and devices where frequently joining between them and to other alloys as austenitic stainless steel is required. However, permanent joining of NiTi to stainless steel is problematic due to the formation of Fe–Ti intermetallics. Pulsed laser welding was studied to join thin foils of NiTi in similar and dissimilar joints to stainless steel. Joining NiTi to NiTi was succeeded with no weld defects. When joining NiTi to stainless steel, it was found that the material impinged by the laser determined the weld pool shape and structure, and it was better when the stainless steel foil was placed below the laser, because nickel enrichment of the weld pool was found to minimise cracking. The factors controlling the weld pool composition and, consequently, the quality of the weld were investigated and discussed.     

Assessment of precipitates of isothermal aged austenitic stainless steel using measurement techniques of ultrasonic attenuation

AISI 316L stainless steel is widely used as a structural material of high temperature thermoelectric power plants, since austenitic stainless steel has excellent mechanical properties. However, creep damage is generated in these components, which are operated under a high temperature and high pressure environment. Several researches have been done on how microstructural changes of precipitates affect to the macroscopic mechanical properties. And they investigate the relation between ultrasonic parameters and metallurgical results. But, these studies are limited by experiment results only. In this paper, attenuations of ultrasonic with isothermal damaged AISI 316L stainless steel were measured. Also, simulation of ultrasonic attenuation with variation of area fraction and size of precipitates were performed. And, from the measured attenuations, metallographic data and simulation results, we investigate the relations between the ultrasonic attenuations and the material properties which is area fraction of precipitates for the isothermal damaged austenitic stainless steel specimens. And, we studied parametric study for investigation of the relation between ultrasonic parameters and metallurgical results of the isothermal damaged AISI 316L stainless steel specimens using numerical methods.     

TIG焊熔池表面流动行为的研究

针对钨极惰性气体保护(Tungsten inert gas,TIG)焊熔池表面流动行为,在确定TIG焊熔池表面可采用粒子示踪的方法来进行其表面流动行为示踪的基础上,在以激光为试验背光光源,通过激光在TIG焊熔池表面镜面反射后,使得熔池及示踪粒子清晰成像于成像屏上。在此基础上,开展对304不锈钢和Q235普通碳钢的熔池表面流动行为的试验研究,对所获得这两种材料的TIG焊熔池试验数据进行处理与对比分析,探究熔池表面流动规律。研究结果表明:在TIG焊过程中,其焊接熔池存在两种运动模式,在304不锈钢焊接过程中熔池表面的液态金属由边缘向熔池中心流动;在Q235碳钢焊接过程中熔池表面的液态金属不定向、不规则地由熔池中心向熔池边缘流动,并测量304不锈钢TIG焊过程中熔池表面的液态金属流动速率为12 mm/s左右,Q235碳钢的熔池表面的流动速率为15 mm/s左右。     

Laser-arc hybrid welding of wrought to selective laser molten stainless steel

Selective laser melting (SLM) is a successful tool-free powder additive technology. The success of this manufacturing process results from the possibility to create complex shape parts, with intrinsic engineered features and good mechanical properties. Joining SLM steel to similar or dissimilar steel can overcome some limitations of the product design like small dimension, undercut profile, and residual stress concentration. In this way, the range of applications of the SLM process can be broadened. In this paper, the hybrid laser welding of selective laser molten stainless steel was investigated. A high-power fiber laser was coupled to an electric arc and austenitic stainless steel wrought and SLM parts were welded together. The power and speed parameters were investigated. The joints were analyzed in terms of weld bead profile, microstructure, microhardness, and tensile test. The efficiency of the welding process was evaluated through the line energy input versus the weld molten area.