Direct keyhole laser welding of aluminum alloy AA5754 to titanium alloy Ti6Al4V

Abstract

is an open access repository that collects the work of Arts et Métiers ParisTech researchers and makes it freely available over the web where possible. a b s t r a c tThe tensile strength of direct AA5754/Ti6Al4V joints performed by high speed Yb:YAG laser welding is found to be determined by morphology and phase content of dissimilar interface formed between contacting Al-rich and Ti-rich melted zones. Three types of contact interfaces were observed: (1) Maximal linear tensile force (220 N/mm for 2 mm thick weld) can be attained when thin contact interface is formed. In this case, the fracture starts in intermetallics-rich zone but propagates mainly in Al-rich melted zone, when in other cases it occurs in brittle intermetallic layers.

Design of Laser Welding Parameters for Joining Ti Grade 2 and AW 5754 Aluminium Alloys Using Numerical Simulation

“…This value is approximate because it does not take into account the variation of thickness of the weld joint compared to the thickness of base materials. On the other hand, the authors observed the tensile strength of 120 MPa when the laser beam was offset to the aluminium alloy [7]. This tendency was confirmed also by laser brazing of Ti6Al4V titanium alloy to A6061 aluminium alloy [44] or laser weld brazing of titanium Grade 2 to AW 5083 aluminium alloy using 5087 aluminium filler wire [45].…”

“…Tomashchuk et al [7] found that the linear tensile force measured during tensile testing of weld produced with beam offset towards Ti6Al4V titanium alloy led to the value of 120 N/mm. The division of this value by the original thickness of welded sheets (2 mm) provides the value of UTS at the level of 60 MPa.…”

“…Laser offset welding was demonstrated to be a promising technique to join dissimilar metals, being capable of producing effective bonding with good tensile strength [6]. The use of higher welding speeds (>4 m⋅min −1 ) would minimize the interdiffusion between the molten materials and reduce the development of brittle intermetallic zones [7].…”

Joining of dissimilar materials

“…Tomashchuk et al [246] show an example of Keyhole laser beam welding of aluminium alloy AA5754 to titanium alloy Ti6Al4V. They investigated the effects in IMC from rapid thermal cycles, different morphologies of contact interfaces, and laser beam positions.…”

Microstructures and Mechanical Properties of Dissimilar Al/Steel Butt Joints Produced by Autogenous Laser Keyhole Welding

“…Although the use of filler wires or flux leads to some improvement in the joint properties, laser welding with filler materials has usually been considered too difficult for industrial applications because there are too many parameters and the requirements for wire positioning are too stringent [28], thereby reducing efficiency and productivity. Thus, the possibility to work in autogenous laser keyhole welding is of important technological interest, as it allows a reduction of the time taken in joint preparation and has fewer parameters to control, making it easier to obtain reproducible and stable results [29].…”