Search

Cold working layers during additive manufacturing improves toughness by imparting a complex glocal integrity across pre-designed internally reinforced domains. Understanding mechanical behavior by mapping glocal integrity across these domains is difficult due to highly heterogeneous compositions formed by cyclic printing and peening. Ultrasound is proposed as a rapid, non-destructive tool to measure glocal integrity that is sensitive to heterogeneous organization of microstructure and residual stress. This work examines compressive behavior and measures glocal integrity with ultrasonic wave speed and attenuation perpendicular to the build direction after cyclically coupling laser engineered net shaping (LENS®) with laser peening on 420 stainless steel. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of the laser in laser assisted jet ECM (LAJECM) is to localise machining to specified areas so that precision and the productivity is improved. Temperature is a predominant determinant of this localisation effect and must be carefully monitored to avoid any heat affected zones or spark damage due to electrolyte boiling. This paper investigates the thermal effects in LAJECM on several alloys by temperature distribution modelling and experimental analysis. The laser influence on material micro removal has led to 25μm deeper cavities with a reflective surface of roughness 20nm R a, without any detectable heat affected zone. [Copyright &y& Elsevier]

Laser-assisted jet electrochemical machining (LAJECM) is a hybrid process, which combines a relatively low-power laser beam and an electrolyte jet. Compared to single jet electrochemical machining, LAJECM yields better machining efficiency and precision, especially for small hole machining. The laser beam transfers additional heat on to a specific area of the workpiece area resulting in changed machining conditions. This localisation effect of machining is the key to improving accuracy and efficiency of the LAJECM. This paper presents also a mathematical modelling of the LAJECM process supported by experimental analysis. [Copyright &y& Elsevier]