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The company launched this technology in 2013 with a smaller model, the Lasertec 65 3D hybrid. Since that time the global machine tool manufacturing group has become a leader in supplying machines for additive production of metal parts.

Gradually the machine range has been extended; first with the Lasertec 4300 3D hybrid combining additive manufacturing using a powder nozzle and turn-mill machining in one work area, and then with powder bed machines in the Lasertec SLM series.

Based on DMG Mori’s rigid monoBLOCK platform, the Lasertec 125 3D hybrid offers high dynamics, rapid build rates and excellent repeatability. Automatic changeover between laser deposition welding and simultaneous 5-axis milling in a single set-up reduces processing times by up to 80%. Such savings are helped by eliminating the need for heat treatment as a separate process step due to the machine's ability to deposit material with a hardness of up to 63 HRC.

The alternate use of laser deposition welding and simultaneous 5-axis milling is beneficial for improving production processes or enabling new component geometries, an example being the manufacture of closed impellers. Another strength of the hybrid machines is the production and repair of hot and cold forming and forging dies.

The Lasertec 125 3D hybrid can also produce lightweight structures that reduce the weight of parts by up to 90%. A selling point of laser deposition welding is the possibility it offers to change between two materials quickly under CNC systems.

So, for instance, hard surfacing to reduce wear can be carried out in one area and corrosion-resistant welding for environmental protection may be carried out in another. Alternatively, the cooling characteristics of a part can be significantly increased. As an illustration, a die casting mould can be produced by starting with a bronze core that dissipates heat effectively and welding onto it an outer skin of tool steel.

In the past five years, such machines have emerged as a key procedure for economical repair and recoating. The damaged area is first prepared by milling before the repair is carried out by laser deposition welding. The part is then finished in a final milling process, all in a single set-up.

The individual processes are thus combined in one machine without compromising other production resources. Due to precise process control, the weld material deposited is of very high quality. The service life of repaired inserts for a die casting mould, for example, is three times longer than if it had been repaired by manual welding.

Another use of the procedure is in areas where top priority must be given to plant availability and reduced maintenance times. These include industries such as oil and gas as well as the chemical, pharmaceutical and energy sectors.

As with its sister models, the Lasertec 125 3D hybrid can be integrated into a CAD/CAM process chain that contributes significantly to raising productivity. High-performance hybrid CAM software for powder nozzle technology, developed especially for DMG Mori by Siemens NX, enables end-to-end programming of repairs with users able to change seamlessly between machining and laser deposition welding during programming. The process steps are sent to the machine in one program and executed alternately in automatic operation.

AM Assistant is part of the innovative software and hardware offer. It includes an integrated thermal imaging camera for continuous monitoring, either of the entire component or defined areas, monitoring of the melt pool size and temperature, or monitoring of the clearance between nozzle and component.

Threshold values for all relevant parameters such as powder volume, working distance or inert gas volume can be stored using the input window AM Guard. If values drift outside preset limits, the build job is interrupted and restarted after a correction has been made. Reject rates due to process parameters that are not optimal are therefore minimised.

AM Evaluator software is an intelligent downstream evaluation tool for 3D process data. It can graphically display stored 3D data from the production process for evaluation purposes. Data from the melt pool analysis, powder flow monitoring and laser power can be analysed individually and compared with each other and with previous build jobs. Automatic generation of reports for quality assurance is available.

DMG Mori www.dmgmori.com