铜及铜合金氩弧焊激光焊说明.doc

铜及铜合金氩弧焊激光焊说明 铜及铜合金焊接 由于铜的导热系统数大, 热容量也大, 焊接时热量迅速从热区传导出去, 使母材和填充材料难以熔合,因此焊接时, 必须采用大功率热源, 必要时, 还要采取预热措施。对于薄板来讲，选用加热面积小、能量密度大、功率大的焊接方法较好。现有针对铜及铜合金板材的焊接较常用的为钨极氩弧焊，采用激光焊接的较少。 1 钨极氩弧焊 钨极电弧非常稳定，特别适合薄板材料焊接，填充焊丝不通过电流，焊接过程中不会产生飞溅，焊缝成形美观;但钨极承载电流能力差，过大的电流会引起钨极的熔化和蒸发，其熔化的微粒可能进入熔池而引起焊缝夹杂;另外，钨极氩弧焊具有熔敷速度小，熔深浅和生产效率低缺点。 [1]针对焊接轧制成型管中的纵焊缝，张健关于薄板(板厚,1mm)高速 TIG 焊温度场的数值模拟的研究中表明，采用直流TIG焊接紫铜板取得了较好的效果，其工艺如表1，其焊缝宽度约为1.0mm，如图1 a和b，焊缝成形质量较好。 表1 直流TIG焊接工艺参数 焊接电弧钨极直径钨极至工件的电弧加热有效半焊接速度电流电压/mm 距离/mm 径/mm m/min /A /U 1 3 3 80 10 10 针对薄板轧制成型管焊接成形焊缝，TIG焊接可以作为其中的一种焊接方式。 a b 图1 焊缝宏观照片 volunteers management. Peace volunteer work is a new thing, the units to be in accordance with a person of a file, a file in a, the establishment of peace volunteers archives. One is before the end of the police station to set up not less than 30 people in the township of peace volunteer service team, pennants, volunteer badges and other equipment to produce their own, specific issues can and propaganda section. The second is the police station monthly planning of not less than two times of peace volunteers propaganda of public security or preventive security activities, fully mobilize the power of the masses, Hong Yang spirit of volunteerism, transfer safe positive energy. Third, the police will have to combine the police real . joint publicity department or the police station, a month to organize carry out more than once to highlight the theme of peace volunteer service activities, such as, the legal system to highlight the legal publicity and education of the youth theme, Interpol, to highlight the narcotics, anti-theft, anti cheating theme, investigation to prominent anti-counterfeiting, anti illegal fund-raising, financial fraud prevention, anti embezzlement etc. theme and security to prominent fireworks governance, management of hazardous chemicals, public security management, network security to give prominence to network security and other topics, household registration, entry and exit to highlight the the