Laser hardening is a common way of using heat treatment to enhance the hardness of metal. Benefiting from the characteristics of laser beams, including focus intensity, the risk of material distortion is lowered and the time needed for processing shortened. These properties also make lasers the perfect fit for complex components, which often require high precision. As a result, laser hardening is widely applied to precision metal processing in industries such as aerospace and automotive.



Laser hardening applies highly intensive energy to a surface that is composed of a certain amount of steel until it reaches the temperature needed for austenitization. The surface then self-quenches rapidly through conduction and hardens. For this treatment, the duration and the temperature of heating are critical factors determining the quality of the result. The process relies heavily on experienced personnel and is difficult to control precisely. Moreover, personnel are exposed to an extremely hot environment, which often results in a high risk of heat illness.



To solve these problems, Delta developed the Automated Laser Hardening Solution for a screw manufacturer in Tainan, Taiwan. On-site personnel simply need to configure parameters and select projects through the Human Machine Interface DOP-100 Series, and leave remaining tasks to the equipment.



The PLC-Based Multi-Axis Motion Controller DVP-MC Series has the Servo System ASDA-A2 Series move the laser head to an exact position for standby. When the sensor detects the screws are ready, the SCARA Robot 40L Series starts to feed the material.



When materials are correctly placed, the PLC-Based Multi-Axis Motion Controller DVP-MC Series commands the Servo System ASDA-A2 Series to rotate the tray and position the screw at the front of the laser beam for heating. Another axis of the ASDA-A2 Series keeps the jig rotating to ensure the uniformity of heating. 



The system automatically controls the processing time to achieve a standard and precise temperature. On the tray two laser modules are installed so the system can process two screws at a time. The SCARA Robot 40L Series also continues to load/unload the materials, which further increases overall efficiency. 



The implementation of Delta’s Automated Laser Hardening Solution provides the client with the following benefits:



• High precision and speed to optimize productivity and quality:

The SCARA Robot 40L Series allows precise positioning and high-speed movement with programmable control. Additionally, the Servo System ASDA-A2 Series has a relative encoder integrated to achieve precise positioning at low speed operation. 



• Fast handshaking and real-time equipment status display through Modbus: 

As the whole solution is composed of Delta’s products, which mostly support Modbus, the SCARA Robot 40L Series can communicate smoothly with other devices. This feature allows the Human Machine Interface DOP-100 Series to communicate quickly with the PLC-Based Multi-Axis Motion Controller DVP-MC Series and display equipment status in real-time.



• Simple wiring and operation with higher flexibility:

The Human Machine Interface DOP-100 Series supports Lua language. With a built-in library and templates, programming and debugging is easier than ever. The PLC-Based Multi-Axis Motion Controller DVP-MC Series and the Servo System ASDA-A2 Series, support CANopen, and allow simple wiring while lowering the cost of implementation.



By achieving precise control of processing time and temperature, Delta’s Automated Laser Hardening Solution enhances production quality and stability of screw hardening. Since the heat treatment is carried out completely by automated equipment, personnel are no longer subject to hot conditions and can devote their time to other processes with higher value.