氮基可控气氛连续纤焊炉成套设备的研制

研制的氮基可控气氛连续钎焊炉,成功地解决了钢质零件的铜钎焊问题。是具有发展前途的新型钎焊设备。     

氮基可控气氛连续钎焊炉成套设备的研制

研制的氮基可控气氛连续钎焊炉 ,成功地解决了钢质零件的铜钎焊问题。是具有发展前途的新型钎焊设备。     

新型推链式可控气氛钎焊炉的研制

新型推链式可控气氛钎焊炉,在国内首次采用了在氮基气氛保护下,应用液氮自动喷淋冷却,一次性完成工件钎焊、光亮淬火的新工艺。本文重点介绍了该炉温度控制系统、碳势控制系统及冷却系统     

不锈钢与铝炉中钎焊保护气体选择的研究

通过对钎焊过程中金属氧化物稳定性及其还原机理的分析,表明在炉中钎焊异种金属不锈钢与铝的过程中,选择合适的保护气氛有利于获得稳定的焊接质量。选择还原气体氨分解气(或氢气)作保护气氛,有助于钎焊过程顺利进行,但使用时存在安全问题。炉中钎焊不锈钢与铝使用钎剂时,无论采用氨分解气还是惰性气体纯氮气作保护气氛,对焊接质量几乎无影响,钎焊样品的焊缝强度均可达65MPa。选择惰性气体氮气作保护气氛,可极大地提高钎焊过程的安全性,并降低成本。     

连续式气体保护钎焊炉的发展现状及其应用

介绍了连续式气体保护钎焊炉的发展现状及其在我国汽车散热器、汽车零部件制造业的应用情况     

铜基新焊料的开发应用

介绍了一种新的铜基焊料的开发应用情况。新焊料的力学、物理与焊接性能完全能满足电子工业中铜和低碳钢（０８Ｆ）的焊接要求，该焊料适用于手推动钎焊炉的钎焊，可取代传统工艺采用的ＨＬＡｇＣｕ５０焊料，达到降低成本和节银的目的。     

钎焊金刚石工具的研究现状与展望

从钎焊工艺、钎焊料、工具产品和生产自动化4个方面介绍了当前国内外钎焊金刚石工具的研究成果，并在此基础上对钎焊金刚石工具下一步的研究重点进行了展望。详细论述了钎焊温度、保温时间、钎料合金成分对钎焊金刚石的影响。适宜的钎焊温度和保温时间可以保证金刚石/钎料界面发生充分反应，界面结合强度增强，获得较好的钎焊接头质量。添加适量的元素或化合物改进钎料合金成分，可以调控钎料的性能，降低金刚石石墨化和热损伤程度。概括总结了常规钎焊金刚石工具、磨粒有序排布钎焊金刚石工具及细粒度钎焊金刚石工具的发展现状，钎焊金刚石工具具有电镀和烧结金刚石工具无可比拟的优点；金刚石有序排布会提高工具的加工效率和使用寿命，提高磨削表面质量；对细粒度钎焊金刚石工具亟待解决的磨粒等高性和分布均匀性问题的研究进行了概述。     

镁合金钎焊技术的研究现状与发展

简要介绍了镁合金钎焊的难点,综述了近年来国内外镁合金钎焊的研究进展,简单分析了焊缝成形及接头组织和性能的影响因素,并对镁合金钎焊技术和材料的发展趋势进行了展望。     

电子元件引线的可焊性

本文报道有关软钎焊问题。可焊性是由于润湿作用,使基体材料与焊料之间有一种冶金结合。在一定的钎焊时间与供热条件下,若焊料与焊剂已选定,则最终可焊性取决于基体材料的表面状态。分析了润湿性的评判方法、焊料中杂质元素的影响及钎焊质量的控制,还讨论了焊料、焊剂、引线材料及保护涂层、钎焊方法等方面的发展动向。     

钎焊箔轧制变形及包覆率变化的遗传规律研究

研究了钎焊箔材料在复合及轧制过程中金属的变形规律,根据金属流变原理,对试验结果进行回归和方差分析,找出钎焊箔材在复合及轧制过程中包覆率变化的遗传规律,对工厂优化钎焊箔生产工艺起重要的指导作用.     

Cr5Mo管焊接工艺

焦油管式炉辐射管材质为Cr5Mo，其体积庞大，形状特殊，焊接质量要求较高，作业环境差，施工难度大。根据现场实际，通过焊接试验，得出较合理的焊接参数，制定出切实可行的焊接工艺，以保证辐射管的焊接质量。     

电动轮汽车关键部位裂纹的应急处理

电动轮汽车的许多关键部位都是用高锰钢材料制作而成。对关键部位裂纹的焊接处理,在采用"正火处理焊缝"方法之后,能有效消除焊接应力,提高焊缝及附近区域的综合机械性能,满足正常生产的需要。     

Laser welding in the dental laboratory: an alternative to soldering

Only recently has laser welding been applied to dental technology, primarily as an alternative to soldering. This article addresses how the laser is used for welding, the effect welding has on metals as the energy is converted into heat and reacts with the alloy's surface and the practicality of laser welding in the dental laboratory. A step-by-step procedure for accomplishing laser-welded connections in a fixed partial denture is included. A laser-welded clasp repair using wrought wire and the addition of custom cast parts welded to an existing removable partial denture framework on the master model are also shown.     

车体铝合金线槽无焊丝塞焊工艺研究

在原有焊接工艺特点的基础上,针对车体铝合金线槽2mm薄板的焊接特点,通过减小焊接电流、增大焊接间隙、改焊丝填充塞焊为母材填充的方式,对车体线槽焊接工艺进行了优化试验研究。结果表明：采用电流为90A、母材突出为1．5mm,装配间隙为1mm的焊接工艺可以获得较好的效果。该工艺不但减少了产品的焊后变形、避免了产品焊穿现象的发生、增大了焊缝熔深,同时,降低了产品的生产成本,提高了劳动工作效率,对于提高类似产品的质量及生产具有积极的作用。     

X65管线钢带状组织对焊接性能的影响

研究了X65管线钢不同级别带状组织对焊接接头的显微组织和力学性能的影响.试验结果表明,焊接接头焊缝处有典型的焊缝组织贝氏体,热影响区含有少量的魏氏体、珠光体、晶内成核铁素体和多边形铁素体组织,焊接接头的拉伸断裂部位在焊缝处;带状组织越严重,焊接后的钢板强度和韧性均变差,因此在X65管线钢生产中要严格控制带状组织的形成.     

Mechanical and elemental characterization of solder joints and welds using a gold-palladium alloy

PURPOSE: This study was conducted to determine whether newer infrared or laser welding technologies created joints superior to traditional furnace or torch soldering methods of joining metals. It was designed to assess the mechanical resistance, the characteristics of the fractured surfaces, and the elemental diffusion of joints obtained by four different techniques: (1) preceramic soldering with a propane-oxygen torch, (2) postceramic soldering with a porcelain furnace, (3) preceramic and (4) postceramic soldering with an infrared heat source, and (5) laser welding. MATERIAL AND METHODS: Mechanical resistance was determined by measuring the ultimate tensile strength of the joint and by determining their resistance to fatigue loading. Elemental diffusion to and from the joint was assessed with microprobe tracings. Scanning electron microscopy micrographs of the fractured surface were also obtained and evaluated. RESULTS: Under monotonic tensile stress, three groups emerged: The laser welds were the strongest, the preceramic joints ranged second, and the postceramic joints were the weakest. Under fatigue stress, the order was as follows: first, the preceramic joints, and second, a group that comprised both postceramic joints and the laser welds. Inspection of the fractographs revealed several fracture modes but no consistent pattern emerged. Microprobe analyses demonstrated minor diffusion processes in the preceramic joints, whereas significant diffusion was observed in the postceramic joints. CLINICAL IMPLICATIONS: The mechanical resistance data conflicted as to the strength that could be expected of laser welded joints. On the basis of fatigue resistance of the joints, neither infrared solder joints nor laser welds were stronger than torch or furnace soldered joints.     

309L焊接用奥氏体不锈钢线材的生产实践

通过对化学成分进行合理优化内控,经特定的生产工艺流程,成功研制了309L焊接用奥氏体不锈钢线材。在研发过程中,开发了适宜于极低碳不锈钢的四元渣系的单渣法精炼工艺（CaO-SiO2-MgO-Al2O3）,解决了冶炼时跳碳问题,使单渣法冶炼操作效果达到双渣法相当的脱硫脱氧效果,通过合理的轧制工艺,解决了不锈钢中因铁素体含量较高而热塑性极差易开裂、宽展大易出耳子的问题,从而大大提高了产品的成材率和表面质量。用户反馈利用309L焊接用不锈钢线材生产的焊条和焊线经使用后结果表明焊接性能良好。     

Results of laser tissue soldering in vasovasostomy and epididymovasostomy: experience in the rat animal model

The use of microsurgical techniques (vasovasostomy and epididymovasostomy) for vasectomy reversal has now enabled surgeons to perform both procedures with certainly acceptable success rates. However, these operations are technically demanding and require special training in microsurgery. PURPOSE: A new method of performing these procedures using laser tissue soldering is described and results are evaluated. Laser tissue soldering is different from laser welding in that it involves the laser activation of a protein solder with a dye specific for the specific wavelength of laser light; therefore, surrounding tissue is not affected by the laser. MATERIALS AND METHODS: Ten rats underwent bilateral vasovasostomy and eleven underwent bilateral epididymovasostomy. In each rat, a sutured anastomosis was performed on one side while laser tissue soldering was performed on the other. Animals were sacrificed after one month and anastomoses were evaluated for patency and presence of sperm granulomas. Histologic analysis was also performed. RESULTS: Patency rates were 8/10 (80%) for sutured vasovasostomy versus 9/10 (90%) for the laser technique. Epididymovasostomy patency rates were 8/11 (73%) for sutured versus 9/11 (82%) for the laser technique. Mean operative times were significantly shorter for lasered anastomoses when compared to controls. The frequency of granuloma formation did not significantly differ between laser and control groups. CONCLUSIONS: Laser tissue soldering resulted in similar patency when compared to a conventional 2 layered sutured anastomosis while decreasing operative time. In addition, since fewer sutures are placed, the laser method is less technically demanding.     

Effect of optical temperature feedback control on patency in laser-soldered microvascular anastomosis

Feedback control has been postulated to improve the efficacy of laser welding in microsurgery, but alteration of outcome has not been clearly shown. The authors evaluated the ability of an optical closed loop temperature feedback control to improve patency, aneurysm rate, and to histologically limit thermal damage. Rat femoral artery anastomoses were performed under operating microscope magnification. One hundred and twenty-four anastomoses were performed in five groups using 1) free-hand (FH) 1.9-microm laser soldering without feedback; 2) temperature controlled (TC) 1.9-microm laser soldering with optical feedback; 3) FH 808 nm laser; 4) TC 808 nm laser soldering; and 5) 10-0 nylon suture control. In Groups 2 and 4, an optical feedback system controlling laser exposure to produce a preset temperature was used. Anastomotic time was significantly less for all laser groups (p < 0.05). Late patency for all 1.9-microm laser anastomoses was almost 0. Temperature controlled 808-nm anastomoses showed no significant difference from sutures in terms of patency (88 percent vs. 96 percent), bursting pressure, and aneurysm rate, while freehand 808-nm anastomoses had a significantly lower patency (71 percent) and more tissue damage (ANOVA, p < 0.05). The authors conclude that temperature control improves outcome in microvascular anastomosis by reducing transmural thermal injury caused by variations in surgeon technique.     

高频感应燃烧红外吸收法测定焊接药剂中硫含量

研究了高频感应燃烧红外吸收法测定焊剂、焊条药皮和药芯焊丝药粉等焊接药剂中硫含量的方法。最佳工作条件为先将0.1~0.15g样品加入预先放置有0.3~0.5g铁屑的瓷坩埚中,再覆盖0.2g锡粒和1.7g钨粒;采用0.3~0.5g钢铁有证标准样品建立校准曲线(助熔剂为0.2g锡粒-1.7g钨粒)。结果表明,方法的测定下限为0.005%(高纯氧气)至0.008%(普通氧气)。将实验方法用于不同硫含量的焊接药剂实际样品的分析,结果的相对标准偏差(RSD,n=6)不大于7%,加标回收率为83%~107%。采用焊剂及矿石标准样品进行准确度验证,测定值与认定值相符合。