濟南鍍鋅板的焊接性能與未鍍鋅的同種鋼板相比有明顯的特殊性。雖然鋅層厚度對于鋼板板厚來說非常小，但是對于焊接性能的影響卻很大。激光搭接焊中搭接板間隙間的鋅蒸氣將流向熔池部位，干擾熔池液相流動，造成飛濺和氣孔，甚至出現(xiàn)嚴重的咬邊等。

The welding performance of Jinan galvanized steel sheet has obvious particularity compared with the same kind of steel sheet without galvanizing. Although the thickness of zinc layer is very small for the thickness of steel plate, it has a great influence on the welding performance. In laser lap welding, the zinc vapor between the lap plate gaps will flow to the molten pool, interfere with the liquid flow in the molten pool, cause spatter and porosity, and even serious undercut.

濟南鍍鋅板

Jinan galvanized sheet

鍍鋅板激光焊特征及缺陷：根據(jù)焊接機理，激光焊可分為兩類即熱傳導焊與深熔焊。由于光斑尺寸差異，兩者能量密度差別很大，前者主要用于材料的表面熱處理，而后者在焊接領(lǐng)域應用廣泛。激光深熔焊的本質(zhì)特征為小孔效應，由于存在小孔，激光束能深入到材料內(nèi)部，被熔化的液態(tài)金屬環(huán)繞在小孔周圍，激光對材料的熱輸入主要是在小孔壁上的液化界面上，隨著激光束的移動，小孔前沿的金屬被熔化、汽化，而在小孔后部，液態(tài)金屬重新凝固形成焊縫，從而完成焊接過程。

Characteristics and defects of laser welding of galvanized sheet: according to the welding mechanism, laser welding can be divided into two categories, namely heat conduction welding and deep penetration welding. The former is mainly used for surface heat treatment of materials, while the latter is widely used in welding field. The essence of laser deep penetration welding is keyhole effect. Because of the keyhole, the laser beam can penetrate into the material, and the molten liquid metal surrounds the keyhole. The heat input of the laser to the material is mainly on the liquefying interface on the wall of the keyhole. With the movement of the laser beam, the metal in the front of the keyhole is melted and vaporized, while the liquid metal in the back of the keyhole is solidified again to form welding To complete the welding process.

激光焊接鍍鋅板的一個基本特征是產(chǎn)生等離子體，等離子體嚴重地阻礙激光束，降低板材對激光能量的吸收，不利于深熔焊時形成小孔及保持穩(wěn)定；另一個特征就是在焊接過程中會形成鋅蒸氣，在對接接頭中，鋅蒸氣在鋼板的上、下表面可以自由膨脹散發(fā)到空氣中去，而且鋅燒損區(qū)域很小，一般為12mm(小于板厚)，接頭的抗腐蝕性能沒有受到太大損害。在激光搭接焊時，鋼板間的鋅蒸氣很容易進入到熔池中去，產(chǎn)生一系列焊接缺陷，弱化接頭性能。

One of the basic characteristics of laser welding galvanized sheet is the generation of plasma, which seriously obstructs the laser beam and reduces the absorption of laser energy, which is not conducive to the formation of small holes and maintaining stability in deep penetration welding; another feature is the formation of zinc vapor in the welding process. In the butt joint, zinc vapor can freely expand on the upper and lower surfaces of the steel plate and emit into the air Moreover, the zinc burning area is very small, generally 12mm (less than the plate thickness), and the corrosion resistance of the joint is not greatly damaged. In laser lap welding, the zinc vapor between steel plates is easy to enter into the molten pool, resulting in a series of welding defects, weakening the joint performance.