Experimental Study On Laser Cladding Repair Of Titanium Alloy

Titanium alloy has excellent performance with wide application prospects in theaviation,aerospace,energy,chemical industry,automotive,medical equipment and other fields.Laser cladding repair is an advance repair technology that has been developed based on Lasercladding.It uses laser beam to make the cladding and substrate form metallurgical bondingand in order to repair the original dimension and properties. It has higher speedcooling,smaller heat affected zone,process is easy to realize automation and otheradvantages.Therefore,there is meaningful application for laser cladding repair orremanufacturing on parts of titanium alloy.In this paper laser cladding repair BT20 alloy were researched by using 5kw crosscurrentCO2 laser.The main contents are as follows:(1)Single-track and single-layer cladding of BT20 alloy was experimented using singlefactor.Three effect of the parameters of laser cladding repair(laser power,scanning speed andpowder feed rate)to the height and width of single-track and single-layer cladding werestudied and then using orthogonal experiment method to find a group of best parameters forsingle-channel and single-layer laser cladding repair which prepared for the multi-track andmulti-Layer cladding experimentations.(2)Multi-track and multi-layer cladding were obtained using single factor experimentmethod which in order to investigate the two parameters scanning spacing and slice height.Itoptimized the laser cladding parameters and then gained optimal combination of parameters .(3)Analysis the sample which were repaired using BT20 powder by laser claddingrepair.firstly,The morphology of cladding surface,the microstructure and micro-hardness ofthe cladding were analyzed.then,The un-standard tensile sample was shaped and the tensiletest was executed.the laser cladding sample and titanium alloy forging’s tensile strength werecontrasted.and then the sample surface residual stress was tested.Finally through it we haverepaired defective venturi with the best combination of parameters and obtain better effects.The above works provide the initial investigation on laser cladding repair of titanium alloy and contribute to the technology’s development.