Increased Productivity and Tool Life Laser Deposition Welding – Economic Reparation
Laser cladding has emerged in many target industries as an excellent technology for repair and coating. This form of additive manufacturing is also popular in the new production of forming and forging tools - i.e. in the hot and cold forming of sheet metal.
Users benefit from laser deposition welding, especially in industries where the focus is not on component costs but on system availability. These include industries such as oil and gas, chemicals and pharmaceuticals. Hybrid concepts that combine laser cladding and conventional milling in one workspace can further increase processing flexibility and productivity. DMG Mori has developed a machine concept that combines conventional cutting with additive manufacturing.
New Machine Concept: Conventional Cutting Meets Additive Manufacturing
The new Lasertec 3D hybrid series combines additive manufacturing using a powder nozzle (also known as DED - Directed Energy Deposition) and 5-axis simultaneous milling in one work area. In laser buildup welding, users can achieve buildup rates of up to 1 kg per hour and a repeatability known from CNC machines. The manufacturing process is accompanied by a software solution from Siemens, which supports the user right from the design phase and process development.
Die Casting Molds with longer Service Life and Improved Cooling Properties
A hybrid production concept offers advantages over existing solutions on the market, particularly in the repair of high-quality die casting molds for the production of aluminum die cast parts. Worn tool molds can be milled off at the neuralgic points and then automatically welded for repair. Thanks to the hybrid concept, the laser head and the milling tool can be exchanged as often as required. This allows users to mill the die casting molds to final dimensions in one operation. Previously, the die cast cores had to undergo a repair process that sometimes took several days. With the help of powder nozzle technology, they can be put back into use within one shift.
This alternating procedure of subtractive and additive machining eliminates the time-consuming part handling of the up to 2,000 kg heavy tool molds and allows complete machining in one clamping. Set-up and idle times are thus reduced to a minimum, so that the repaired die casting mold can be used up to 90% faster. In addition, this machining process increases tool life by up to 300%. Toyota has already been able to prove this in practice by means of the triple service life of its die cast cores compared to the previous manual repair welding process. The use of multi-materials offers further potential for optimization. For example, the tool core can be produced with an alloy that has a 30% higher thermal conductivity than the tool steel in the cover layer. This increases the cooling rate in the die casting process and consequently the output quantity.
Digital Process Monitoring
The hybrid machine concept can be extended by an intelligent software solution. This includes, among other things, an integrated thermal imaging camera for continuous thermal monitoring of the entire component or defined areas, monitoring of the melt pool size and temperature or monitoring of the distance between the nozzle and the component. Via the input mask - limit values can be stored for all relevant process parameters such as powder quantity, working distance or inert gas quantity. If they are exceeded or fallen short of, the construction job is interrupted, which can be restarted without problems at any time after correction. Reject rates due to non-optimal process parameters are minimized in advance. A downstream intelligent evaluation software for 3D process data can also graphically display already stored data from the production process for evaluation. Data from melt pool analysis, powder flow monitoring or laser power can be analyzed individually and compared with each other and with previous construction jobs. The automatic generation of reports for quality assurance in production is also possible. This makes the software solution the ideal companion for additive manufacturing and the prerequisite for increased quality and process reliability along the entire process chain.