We present recent advances of pure copper, copper alloy and precious metal additive manufacturing with green, frequency doubled disk lasers achieved by the exploration of process parameters to specifically address the unique laser processing challenges of this class of high reflective, high conductive materials. Results are presented for the analysis of samples made from pure copper, and from the CuCr1Zr alloy. The material properties density, electrical conductivity, and sample properties as geometrical resolution and surface roughness are presented. Part performance in application is discussed.
A 500°C preheating system is used in multi-laser fusion processes to overcome defect formation, and to successfully manufacture highly dense, crack-free, low distortion parts from 1.2343 hot working steel and aerospace grade Ti6Al4V ELI. With a three-laser opto-mechanical focusing and scanning system, we demonstrate high precision laser metal fusion over 300mm diameter fullfield overlapping scan fields at high productivity. Results of density, surface quality and material properties are presented. Control of oxygen level in parts and powder is demonstrated over multiple powder reuse cycles.
Disk lasers with multi-kW continuous wave (CW) output power are widely used in manufacturing, primarily for cutting
and welding applications, notably in the automotive industry. The ytterbium disk technology combines high power (average
and/or peak power), excellent beam quality, high efficiency, and high reliability with low investment and operating
costs. Fundamental mode picosecond disk lasers are well established in micro machining at high throughput and perfect
precision. Following the world's first market introduction of industrial grade 50 W picosecond lasers (TruMicro 5050) at
the Photonics West 2008, the second generation of the TruMicro series 5000 now provides twice the average power
(100 W at 1030 nm, or 60 W frequency doubled, green output) at a significantly reduced footprint. Mode-locked disk
oscillators achieve by far the highest average power of any unamplified lasers, significantly exceeding the 100 W level in
laboratory set-ups. With robust long resonators their multi-microjoule pulse energies begin to compete with typical ultrafast
amplifiers. In addition, significant interest in disk technology has recently come from the extreme light laser community,
aiming for ultra-high peak powers of petawatts and beyond.