Laser-assisted machining of an austenitic stainless steel: P550

Abstract

High-nitrogen, nickel-free stainless steels have much higher yield strength than typical stainless steels, and their high corrosion resistance and high strength makes them especially attractive in medical, aerospace, and oil drilling industries. The high strength also makes these materials difficult to machine owing to high cutting forces, and relatively short tool lives. Laser-assisted machining (LAM) is investigated as an economic alternative for machining these difficult-to-machine materials. In the current study, surface temperature measurements are compared with model predictions to ascertain the accuracy of a thermal model. An experimental matrix is designed to determine the effects of temperature and surface speed, using tool life, cutting forces, surface roughness, and workpiece integrity as metrics to determine optimal processing conditions. Explanation of cutting temperatures and effects on tool life are discussed. Hardness measurements, X-ray diffraction, and microstructural analysis indicate little or no damage of the subsurface of the workpiece. An economic analysis shows the benefits that can be obtained over conventional machining through implementation of LAM in stainless steels.

Hybrid manufacturing in micro/nano scale: A Review

“…7 A schematic diagram of laser interaction with deposited nanoparticles and the substrate (modified and redrawn from reference 27) turning, with a reduction in the specific cutting energy of approximately 20% compared with no laser heating. 35 In addition, the precision and cutting rates were improved by 400% and 300% respectively, and the volumetric removal rate was improved by 200%. [87][88][89][90][91] The University of Nebraska reported optimum process parameters for high material removal rates.…”

“…[28][29][30][31][32][33][34][35][36][37][38][39][82][83][84][85][86][87][88][89][90][91] The University of Edinburgh, Glasgow Caledonian University, and Philips Dap BV reported hybrid systems that combine focused laser beams for drilling and a jet electrolyte for machining together, as shown in Fig. 8.…”

The development of a novel process planning algorithm for an unconstrained hybrid manufacturing process

“…Dumitrescu et al [15] attempted to use a high power diode laser, suggesting that higher machining efficiency and better metal absorption can be expected. Anderson and Shin [16] proposed a new configuration in which two laser beams simultaneously irradiate a machined chamfer and an unmachined surface adjacent to the chamfer, respectively. It is the simultaneous application of mechanical machining by spindle rotation, and ultrasonic vibration by a high frequency axial ultrasonic oscillation of the cutting tool or workpiece [17].…”

Integrated Process of Laser-Assisted Machining and Laser Surface Heat Treatment

“…However, in the LAM process, the high preheating temperature associated with large plastic deformation may promote undesirable microstructural change on machined surfaces, such as the formation of a white layer [12]. Therefore, the preheating temperature in LAM must be well controlled below the austenitization start temperature TAS in order to avoid workpiece subsurface damage, and at the same time to achieve the maximum benefits of reduced cutting force F^, reduced tool wear and good surface finish [13]. The preheating temperature in LSHT, on the other hand, must be within the austenitization zone, but lower than the melting temperature, to allow for carbon diffusion.…”