Laser additive manufacturing titanium-steel multi-material component having improved interface bonding and formability by suppressing element diffusion through intermediate layer, apparatus and method thereof

A titanium-steel multi-material laser additive manufacturing apparatus having an improved interface bonding and formability by suppressing an element diffusion through an intermediate layer, constructed based on a laser directed energy deposition process, configured to manufacture a titanium-steel multi-material component by laser additive, and comprising a protective chamber, a powder feeder, a working head for printing, a forming substrate and a controller, wherein the working head for printing is integrated with a powder transportation pipe, a laser and a shielding gas transporting pipe;

• the forming substrate is arranged in the protective chamber, the powder feeder contains powder to be printed, the printing powder contained in the powder feeder is transportable to a printing area on the forming substrate through the powder transportation pipe, laser beam spots emitted by the laser are capable of falling on the printing area on the forming substrate, and a shielding gas is transportable to the printing area on the forming substrate through the shielding gas transporting pipe;
• wherein the forming substrate is a titanium alloy substrate;
• the powder feeder contains four types of printing powders, that are, a titanium alloy powder, an elemental metal Ce powder, an elemental metal Cr powder, and a stainless steel powder, correspondingly;
• a powder processing file is created based on the structural characteristics of the titanium-steel multi-material component in the controller, wherein four sets of powder processing data are integrated in the powder processing file, and each set of powder processing data is provided with laser printing process parameters and corresponding laser scanning path planning;
• the four sets of powder processing data are first to fourth set of powder processing data, correspondingly, wherein the first set of powder processing data is used for depositing and melting the titanium alloy powder to form a titanium alloy layer, the second set of powder processing data is used for depositing and melting the elemental metal Ce powder to form an elemental metal Ce layer, the third set of powder processing data is used for depositing and melting the elemental metal Cr powder to form an elemental metal Cr layer, and the fourth set of powder processing data is used for depositing and melting the stainless steel powder to form a stainless steel layer;
• under a control of the controller, after a laser power and a scanning speed of a laser beam output by the laser are controlled according to the laser printing process parameters in the first set of powder processing data, the powder transportation pipe is started to transport the titanium alloy powder contained in the powder feeder to the printing area, then the working head is controlled to actuate according to a laser scanning path planning in the first set of powder processing data until a deposition of the titanium alloy layer is completed on the titanium alloy substrate;
• the type of powder transported by the powder transportation pipe is switched to enable the powder transportation pipe to transport the elemental metal Ce powder contained in the powder feeder to the printing area, and the working head is controlled to actuate according to a laser scanning path planning in the second set of powder processing data until deposition of two layers of the elemental metal Ce layers is completed on the titanium alloy layer, and a type of powder transported by the powder transportation pipe is switched to enable the powder transportation pipe to transport the elemental metal Cr powder contained in the powder feeder to the printing area, and the working head is controlled to actuate according to a laser scanning path planning in the third set of powder processing data until deposition of two layers of the elemental metal Cr layers is completed on the elemental metal Ce layer, and the type of powder transported by the powder transportation pipe is switched to enable the powder transportation pipe to transport the stainless steel powder contained in the powder feeder to the printing area and the working head is controlled to actuate according to a laser scanning path planning in the fourth set of powder processing data until deposition of the stainless steel layer is completed on the elemental metal Cr layers, to obtain titanium-steel multi-material components.

hours to remove water and improve a fluidity of the powder, and placing, after the drying is completed, the powder into the powder feeder;

• a step 2, creating powder processing data:
• creating, based on the laser directed energy deposition process, the four sets of mutually independent powder processing data, and configuring each set of powder processing data with the laser printing process parameters and the laser scanning path planning;
• the four sets of powder processing data being first to fourth powder processing data, correspondingly, wherein:
• the first set of powder processing data is used for depositing and melting the titanium alloy powder to form the titanium alloy layer;
• the second set of powder processing data is used for depositing and melting the elemental metal Ce powder to form the elemental metal Ce layer;
• the third set of powder processing data is used for depositing and melting the elemental metal Cr powder to form the elemental metal Cr layer;
• the fourth set of powder processing data is used for depositing and melting the stainless steel powder to form the stainless steel layer;
• a step 3, placing the titanium alloy substrate into the protective chamber, controlling an industrial robot to adjust the laser focus offset, closing, after the adjustment is completed, a cabin door of the protective chamber, and introducing pure argon to deoxidize;
• a step 4, starting, after an oxygen content in the protective chamber is reduced to 50 ppm, a laser to sequentially deposit different materials on the titanium alloy substrate to obtain the titanium-steel multi-material component with good metallurgical bonding interface, and specifically comprising following steps:
• a step 4.1, loading the first set of powder processing data in the step 2 to deposit the titanium alloy layer on the titanium alloy substrate;
• a step 4.2, adjusting, after the titanium alloy layer is deposited, the laser focus offset by taking a top surface of the titanium alloy layer as a reference, and loading the second set of powder processing data in the step 2 to deposit the two layers of the elemental metal Ce layers on a surface of the titanium alloy layer;
• a step 4.3, adjusting, after the elemental metal Ce layer is deposited, the laser focus offset by taking a top surface of the elemental metal Ce layer as a reference, and loading the third set of powder processing data in the step 2 to deposit the two layers of the elemental metal Cr layers on a surface of the elemental metal Ce layer;
• and
• a step 4.4, adjusting, after the elemental metal Cr layer is deposited, the laser focus offset by taking a top surface of the elemental metal Cr layer as a reference, loading the fourth set of powder processing data in the step 2 to deposit the stainless steel layer on a surface of the elemental metal Cr layer, and eventually obtaining the titanium-steel multi-material component with good metallurgical bonding interface.