Net Shaping (net + shaping)

Distribution by Scientific Domains


Selected Abstracts


Process Cost Comparison for Conventional and Near-Net-Shape Cermet Fabrication,

ADVANCED ENGINEERING MATERIALS, Issue 3 2010
Yuhong Xiong
Tungsten carbide,cobalt (WC,Co) is a widely used cermet that is generally fabricated into bulk parts via conventional powder metallurgy (P/M) methods. Because this material (and other cermets) is very hard and wear resistant, diamond grinding is generally required to fabricate complex parts. As an alternative, studies have shown the Laser Engineering Net Shaping (LENS) process to be a technically feasible method, allowing for fabrication of near-net-shape parts. The economic trade-offs, however, have not been previously characterized. In this work, technical cost modeling (TCM) is applied to compare the costs of fabricating WC,Co parts with the P/M process to those of the LENS process. Cost drivers are identified and sensitivity analysis is conducted. Results reveal that the uncertainty in functional unit has a significant effect on relative process costs, and the cost is sensitive to order size only if less than ten parts are produced. It is concluded that the LENS process is economically preferable if part size is small or part shape is complex. The P/M process is more suitable to produce large parts in simple shapes. [source]


Processing of Bulk Alumina Ceramics Using Laser Engineered Net Shaping

INTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY, Issue 3 2008
Vamsi Krishna Balla
Application of rapid prototyping (RP) in ceramics manufacturing is motivated by advances in engineering ceramics where attaining complex shapes using traditional processing is difficult. Laser Engineered Net Shaping (LENSÔ), a commercial RP process, is used to fabricate dense, net-shaped structures of ,-Al2O3. Shapes such as cylinder, cube, and gear have been fabricated successfully with 10,25 mm section sizes. As-processed structures show anisotropy in mechanical properties with a high compressive strength normal to the build direction and columnar grains along the build direction. Heat treatment did not alter strength and anisotropy, but increased the grain size from 6 to 200 ,m and hardness from 1550 to 1700 Hv. [source]


Compositionally Graded Aluminum Oxide Coatings on Stainless Steel Using Laser Processing

JOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 7 2007
Partha P. Bandyopadhyay
A 1.5 mm thick fully dense alumina coating with a composition gradient from 100% Ni,20 wt% Cr at the substrate to 100% alumina on top has been developed on a 316 stainless steel sheet using Laser Engineered Net Shaping (LENSÔ). The gradient coatings showed hardness in the range of 1800,2000 Hv, one of the highest reported so far due to high-density layers. During laser deposition, ,-Al2O3 found to grow along the deposition direction with coarse columnar structure. The inherent advantage of this approach is to control simultaneously both location and composition leading to better interfacial properties of coatings. [source]