Tailored blank laser welding method for titanium micro-alloying carbon manganese steel

Abstract

The invention discloses a tailored blank laser welding method for titanium micro-alloying carbon manganese steel. Laser is utilized to weld welding positions of titanium micro-alloying carbon manganese steel plates in air or in shielding gas which is a mixture of inert gas and oxygen gas. Weld zones obtained through the tailored blank laser welding method contain titanium elements obtained by melting base metal, titanium elements are oxidized and bonded with oxygen element provided by oxygen in shielding gas or air, formed titanium-containing oxides in proper size can just become nucleation points of acicular ferrite, full penetration welds of a mixed structure of acicular ferrite and martensite are obtained finally, and the welds have higher toughness than welds of a pure martensite structure obtained from pure inert gas. Compared with a method using pure inert gas rather than inert gas and oxygen mixed shielding gas or air, the method has the advantages that usage of inert gas is lowered, welding cost is reduced, and laser welding in air is unrestricted by welding surroundings.

Description

technical field [0001] The invention relates to the technical field of laser welding, in particular to a laser tailor welding method for titanium microalloyed carbon-manganese steel. Background technique [0002] Microalloyed steel is a typical high-strength steel, which has been widely used in automobiles, construction machinery, bridges, high-rise buildings and other fields. This type of steel mainly uses the characteristics of fine grain strengthening, precipitation strengthening, and solid solution strengthening of microalloying elements Nb, V, Ti, Mo, etc. to improve the strength of the steel. [0003] Welding is one of the main ways of joining this steel. As a welding technology with high energy density, laser tailor welding technology has the advantages of small heat input, high welding speed, large depth-to-width ratio of weld seam, high welding quality, and no need to add welding wire. Compared with traditional welding methods such as arc welding, Argon arc weldin...

AI Technical Summary

Problems solved by technology

[0004] When laser tailor welding technology is applied to titanium microalloyed carbon-manganese steel, laser welding is performed under the protection of pure inert gas, and the microstructure of the weld zone forms a single martensite, resulting in low strength and toughness of the weld zone

At the same time, the use of pure inert shielding gas for welding protection increases the welding cost and the welding environment is restricted

Images