In Laser Cladding, a differentiation must be made between cladding by brazing and cladding by welding regarding process parameters and the resulting material properties. Results of investigations of bronze cladding on steel parts produced by Laser Deposition Brazing will be presented. This means that a strong metallurgical bond is realized by diffusion processes by Laser Deposition Brazing, but the steel base material is not molten. The coatings were characterized by hardness distribution measurements from the bronze cladding to the steel substrate, by measuring the size of the heat-affected zone and by porosity measurements. This combination of a steel substrate and a local bronze coating is used industrially in many tribological applications, such as plain bearings or hydraulic pumps etc. The bronze offers excellent tribological properties. In some cases, the bronze is used as a complete solid part. However, applying the bronze locally to a steel base body instead of using a complete solid bronze component, offers the advantage of the higher modulus of elasticity of the steel, which provides greater stability of shape with regard to possible elastic deformations as these coated parts are exposed to high mechanical loads, it is essential that a high coating quality is achieved by laser cladding and that the properties are extensively and purposefully characterized. The production technology, the characterization and the industrial applications of such bronze coated steel parts are presented and explained in this contribution.

Laser cladding shows an increasing interest to apply high-quality tailored surface coatings, as well as 3D-deposits for repair and additive manufacturing of metallic parts. The industry is requesting powerful technologies that maintain the quality advantages of the laser technology, but also make the process more productive, as well as time and cost efficient. At Fraunhofer IWS a Laserline fiber-coupled diode laser of 20 kW power has been employed for over a decade to develop competitive coating solutions. The deposition rates achieved with this technology are comparable to those of common PTA technique, while at the same time bringing significant advantages in terms of reduced heat affected zone, distortion and savings in material resources.

Amorphous alloys have attracted extensive attention due to their unique atomic arrangement and excellent properties. However, the application in practical engineering is seriously limited due to the size, crystallization and other problems. Laser additive manufacturing technology has the characteristics of high heating, cooling rate and point by point melting deposition, which provides a new idea for the preparation of amorphous alloys. Zr 50 Ti 5 Cu 27 Ni 10 Al 8 amorphous alloy was prepared on the surface of pure zirconium substrate by selective laser melting technology. The composition and structure of the samples were characterized. The results show that the samples are mainly composed of amorphous phase, and the crystallization mainly occurs in the superimposed zone of heat affected zone. With the decrease of laser power, the area of crystallization zone and the number of crystallization particles decrease. However, if the laser power is too low, there will be non-fusion defects and cracks, which will seriously affect the forming quality and amorphous rate of amorphous alloy.

The purpose of this study is to determine if a GTAW (TIG) repair weld under an APS ceramic coating would cause a reduction in adhesion strength. Two stainless steels and a titanium alloy were selected for the study. For each material, 300 buttons were machined and further processed in groups of 50 through the application of one-pass, three-pass, or full pad welds. Welded buttons were lapped parallel to within 0.0002 in. and their lengths were compared with measurements obtained from buttons that had not been welded. NiCrMo bond coats were applied by HVOF spraying to both welded and unwelded samples, which were then top-coated with a ceramic layer (Cr 2 O 3 , Cr 2 O 3 -Al 2 O 3 , or TiO 2 ) deposited by air plasma spraying. A ten-cycle heat treatment was conducted on half of the samples to determine if the weld would amplify thermal expansion stresses. Based on adhesion test results, the welding had no measurable effect on adhesion strength nor did the heat treatment. Heat input from the HVOF flame and the plasma jet was sufficient to reduce weld-related solidification stresses.