699 Walsh CH09 8/30/05 10:08 PM Page 699 Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. Sheet Metal Practices and Layout 700 TABLE 9.6 Two Channels with Unstiffened Flanges Back to Back ( Continued ) Walsh CH09 8/30/05 10:08 PM Page 700 Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. Sheet Metal Practices and Layout 701 Walsh CH09 8/30/05 10:09 PM Page 701 Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. Sheet Metal Practices and Layout 702 TABLE 9.7 Two Equal-Leg Angles, Back to Back, Unstiffened Legs Walsh CH09 8/30/05 10:09 PM Page 702 Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. Sheet Metal Practices and Layout 703 Walsh CH09 8/30/05 10:09 PM Page 703 Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. Sheet Metal Practices and Layout 704 TABLE 9.8 Two Equal-Leg Angles, Back to Back, Stiffened Legs Walsh CH09 8/30/05 10:09 PM Page 704 Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. Sheet Metal Practices and Layout 705 Walsh CH09 8/30/05 10:09 PM Page 705 Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. Sheet Metal Practices and Layout 706 TABLE 9.9 Hat Sections Walsh CH09 8/30/05 10:09 PM Page 706 Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. Sheet Metal Practices and Layout 707 Walsh CH09 8/30/05 10:09 PM Page 707 Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. Sheet Metal Practices and Layout 708 TABLE 9.9 Hat Sections ( Continued ) Walsh CH09 8/30/05 10:09 PM Page 708 Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. Sheet Metal Practices and Layout [...]... shows an as-processed Ti-6Al-4V head-mounted display component built via EBM prior to finish machining As is the case with sand castings, critical features are subjected to any necessary finish machining operations Approximately 0.5 to 1.5 mm of material typically is recommended as a machining allowance Finish machining of Ti-6Al-4V parts built with this process has been achieved using TiAlN-coated end... Walsh CH11 8/30/05 10:22 PM Page 729 Source: McGraw-Hill Machining and Metalworking Handbook Chapter 1 1 Hardening and Tempering Steels and Nonferrous Alloys The hardening and tempering of steels and nonferrous alloys are important aspects of metalworking Carbon and alloy steels are relied on to perform a great number of services in the metalworking industries Some of the nonferrous metals and alloys... e.g., ferrite and pearlite in low-carbon steel 11. 3 Standard Definitions of Terms Pertaining to Heat Treatment of Metals Many terms are associated with the heat treatment of metals, and the American Society for Testing and Materials (ASTM) has classified these terms in ASTM Standard E4 4-8 4 Figure 11. 2 outlines the terms and definitions as described in ASTM Standard E4 4-8 4 and is reproduced with permission... The clay-supported pattern is then placed inside a box A suitable release agent is sprayed on the exposed part, clay, and inner box walls 4 The RTV silicone rubber is mixed and degassed according to the manufacturer’s recommendations and then is poured slowly onto the exposed part and clay surface until the liquid level is approximately 25 mm (1 in) above the top of the part The box is set aside and is... glass-filled nylon), direct-inject tooling may last from just a few shots to several hundred shots When the molded part has complex geometry, it is customary to produce a “hand mold.” Rather than assembling a complex tool with hydraulic slides and other moving components, the direct-inject inserts with removable cores are assembled by hand and placed in the mold base The inserts are then removed from... urethane may include dyes and/ or fillers to modify its appearance and material properties Common fillers include glass beads to reduce part weight and to reduce the volume (and cost) of the resin being used Chopped fiberglass strands sometimes are added to increase part strength Metal powders such as bronze are also added at times to make the part look and feel like a metal part Provided the powder loading... removed from the powder bed and placed in a furnace The polymer binder is vaporized under careful control, and the remaining steel particles are sintered The resulting component is porous sintered A6 steel If full density is desired, the part can be infiltrated with a secondary metal such as bronze Figure 10.5 shows a photograph of a well-known rook chess piece that was built in steel and infiltrated... silicone rubber is mixed and poured over the exposed part and RTV surfaces This is allowed to cure for approximately 24 hours 9 Once the rubber has cured, the walls of the box are removed Provided an appropriate release agent has been used, the two cured halves of RTV silicone should just peel apart along the parting line without any need to cut them with a knife 10 The RP pattern is removed, thus leaving... early processes included stereolithography (3D Systems), fused deposition modeling (Stratasys), and selective laser sintering (3D Systems) The SLS process also has been used to make sintered parts from both metal and ceramic powders Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies All rights reserved Any use is subject... the final part and reduces material costs Although titanium and its alloys (most notably Ti-6Al-4V) seem to have attracted the most interest, there also has been considerable development work involving a wide variety of metal-matrix composites (MMCs) involving TiB, TiC, SiC, and other reinforcements The majority of RM processes are powderbased, so particulate-reinforced MMCs are employed rather than . unmelted powder surrounding the part also serves to support any downward-facing surfaces. Parts fabricated via most powder-based RM processes, including EBM, possess textured surfaces somewhat resembling. are used as patterns for investment casting or sand casting. 10.1 Direct-Metal Rapid Manufacturing Processes Recent years have witnessed a flurry of research and development aimed at “direct-metal”. wide vari- ety of metal-matrix composites (MMCs) involving TiB, TiC, SiC, and other reinforcements. The majority of RM processes are powder- based, so particulate-reinforced MMCs are employed rather