金屬激光(guang)焊接機焊接方式的描(miao)述(shu)

激光光束是金屬激光焊接機高效(xiao)焊接(jie)(jie)的(de)(de)關鍵，它具有非常高的(de)(de)熱量，能夠傳遞(di)到(dao)待焊接(jie)(jie)工(gong)(gong)件(jian)(jian)表(biao)面，并且(qie)轉(zhuan)換(huan)成(cheng)熱能使工(gong)(gong)件(jian)(jian)出現熔(rong)化(hua)。當激(ji)光(guang)(guang)光(guang)(guang)束離開工(gong)(gong)件(jian)(jian)表(biao)面時，工(gong)(gong)件(jian)(jian)就能迅速冷卻固化(hua)，實現焊接(jie)(jie)。根據市場上金屬激(ji)光(guang)(guang)焊接(jie)(jie)機焊接(jie)(jie)的(de)(de)實際情(qing)況，可以分(fen)為激(ji)光(guang)(guang)熱導(dao)焊接(jie)(jie)和激(ji)光(guang)(guang)深熔(rong)焊接(jie)(jie)兩種常見(jian)焊接(jie)(jie)方式(shi)。

金屬激光焊接機這兩種焊接方式的區別在于激光功率密度，激光深熔焊接機的激光功率在10⁵~10⁷W/cm²，相(xiang)(xiang)對較高。工(gong)件(jian)吸(xi)收(shou)激(ji)光能(neng)量后，迅速熔(rong)(rong)化甚(shen)至蒸(zheng)發。熔(rong)(rong)化的金(jin)屬(shu)在蒸(zheng)汽壓(ya)力(li)的作用下形(xing)成一(yi)個小孔(kong)。激(ji)光束可以直(zhi)接(jie)照射到孔(kong)的底部，使孔(kong)不斷向深(shen)處延伸，直(zhi)到孔(kong)內的蒸(zheng)汽壓(ya)與(yu)液態金(jin)屬(shu)的表(biao)面張力(li)和重力(li)相(xiang)(xiang)平衡。隨著激(ji)光束與(yu)工(gong)件(jian)的相(xiang)(xiang)對運動(dong)，孔(kong)周圍金(jin)屬(shu)不斷熔(rong)(rong)化、流動(dong)、閉合(he)、凝固，形(xing)成連續焊(han)(han)縫。焊(han)(han)縫深(shen)而(er)窄，熔(rong)(rong)深(shen)與(yu)熔(rong)(rong)寬之比大。一(yi)般金(jin)屬(shu)激(ji)光焊(han)(han)接(jie)機都能(neng)夠(gou)達到5:1的高寬比，厚度相(xiang)(xiang)對較厚的工(gong)件(jian)都會選擇深(shen)熔(rong)(rong)焊(han)(han)接(jie)方式(shi)。

功率密度在10⁵~10⁶W/cm²之間的(de)金(jin)屬激光(guang)焊(han)(han)接機則采用激光(guang)熱(re)傳(chuan)導(dao)焊(han)(han)接方式(shi)。由于(yu)激光(guang)能量(liang)有限，所以工(gong)件吸收激光(guang)能量(liang)后只能在表(biao)面熔(rong)(rong)化(hua)，依靠(kao)熱(re)傳(chuan)導(dao)原理向(xiang)工(gong)件內部傳(chuan)遞熱(re)量(liang)，從而形成熔(rong)(rong)池(chi)。兩個工(gong)件在熔(rong)(rong)池(chi)中(zhong)相互熔(rong)(rong)接，從而完成焊(han)(han)接。由于(yu)熱(re)傳(chuan)導(dao)焊(han)(han)接的(de)熔(rong)(rong)深(shen)較淺，深(shen)寬比(bi)也較小，所以此類金(jin)屬激光(guang)焊(han)(han)接機適合于(yu)厚度(du)較薄工(gong)件的(de)焊(han)(han)接加工(gong)。