Ceramics are widely used in different industries due to their unique physical, electrical or optical properties. Some of them are semiconductors, hence, they have good prospects in a new generation of electronics. Common examples are materials like polycrystalline diamond (PCD), Silicon Carbide (SiC), Tungsten Carbide (WC). However, processing of ceramics is still challenging, especially if it comes to cutting, drilling or surface structuring on a microscopic level. All these materials are typically very hard and brittle. Usage of lasers is beneficial because the process efficiency is not related to material mechanical properties. But not all lasers are equally good for this application. For example, processing of ceramics with CW or nanosecond lasers still leads to creation of micro-cracks inside the volume due to heat accumulation around the affected area. Another issue is debris which is generated during this process and can pollute the surface nearby.
Femtosecond lasers are able to overcome all mentioned shortcomings. Energy concentrated in an extremely short pulse makes the process clean and efficient. Material is heated and evaporated almost instantaneously and energy has not enough time to be transferred to the crystal lattice and distributed around. The risk of microcracks formation is significantly reduced. Special features can be obtained using burst mode. This significantly increases the speed and efficiency of the processing. Additionally, such bursts of tightly spaced pulses can be used to improve the surface quality and obtain lower roughness.
The experimental results confirm that a clean short pulse together with high energy and burst mode are a perfect combination for the best process speed and surface quality combination. All these features are available from our Indylit 10 laser, which was created to eliminate the necessity for compromises in your applications.
Tungsten Carbide (WC) processing
Direct Machining Control, one of our earliest customers of Indylit 10 laser, kindly shared the results of Tungsten Carbide (WC) ceramics processing. Manufactured parts are WC stamps for cutting tools manufacturing. The objective was to achieve required surface quality maintaining the high process throughput at the same time.
The laser was tested in different operation regimes. It was noticed that the usage of burst mode significantly increases the process speed, while the surface quality remains still good. The average surface roughness is in the range of Ra ~ 700 nm. Pictures of the processed parts and their depth profiles are presented below.