R. Bernhard
P. Neef
H. Wiche
V. Wesling
C. Hoff
J. Hermsdorf
S. Kaierle

Laser Cladding - Additive Manufacturing

Springer Nature
Cham
1-8
2020
Type: Buchkapitel
Abstract
Manufacturers and suppliers in the laser industry face worldwide competition. In order to stay in the market and remain competitive, it is necessary to improve products and processes continually. Additive manufacturing of metals has emerged as a potential technology for companies to create highly integrated and individualized products. Predominant in the additive field are two technologies: Laser powder bed fusion (LPBF) and laser cladding, also known as laser metal deposition (LMD). Especially laser cladding has gained popularity for surface treatment and refurbishing. The highly flexible laser process allows repair and reinforcement of valuable structures that would otherwise be scrapped (Gebhardt 2013). Building on this, laser cladding has evolved into a potent three-dimensional additive manufacturing technology by stacking the deposited material layers. Currently a wide variety of materials can be processed. The ability to functionalize surfaces as well as 3D-printed objects leads to further integration of structural, optomechanical and thermal properties into these parts. One approach is the combination and encapsulation of optical elements like quartz lenses or laser crystals with custom alloys, thus creating multi-material components (Bernhard et. al. 2019). The material composition is based on matched mechanical and thermal properties of the materials. Additive manufacturing with laser cladding also offers the opportunity to integrate cooling solutions, which reduce mechanical stresses and improve optical properties of the assemblies. These complex structures lead to increasingly complex processes with narrow process and parameter windows, within which defects can occur. Irregularities in a laser cladding process can range from small pores to larger heat induced cracks as well as bonding defects and cavities. Advanced process monitoring systems and process control has increased the quality of metal 3D-prints significantly. The resulting robust process leverages laser cladding to a well manageable technology for additive manufacturing.