A robust, untroubled grinding process needs safety parameters for tool production [KLOM86, p. 11]. Tool breakage might be caused by wrong tool design, manufacturing defects, inapproriate choice, faulty handling or storage, improper use, and clamping, etc. [DIN11]. Several organizations define safety measures for grinding wheel use, such as Berufsgenossenschaft or OSHA (Occupational Safety and Health […]
Рубрика: Life Cycle and Sustainability of Abrasive Tools
Adhesion
The direct contact of body and counter body can lead to atomic bonds (“micro weldings”), which are defined as adhesion [GAHR87, RABI95]. A relative movement of the contact partners does not necessarily involve that the bonds break within the original contact areas, so that material transfer can happen [HABI80]. Adhesive layers change the friction conditions. […]
Life Cycle Costing (LCC)
The method of Life Cycle Costing has been developed in the USA for calculation of the economic feasibility and design for projects in industrial plant construction [VDI05]. Life Cycle costs include not only the product’s manufacturing costs, but also usage and disposal costs. The grinding costs per part enclose the machine costs, labor costs, tool […]
Energy of Raw Materials
Manufacturing of the abrasives corundum and CBN is described in Chap. 2 “Abrasives”. The energy consumed in their primary production can be estimated Grinding wheel width 20 mm 20 mm Outer diameter 400 mm 400 mm Inner diameter 200 mm 200 mm Segment length — 31.4 mm Segment height — 5 mm Number of segments […]
Corundum
2.1.1 Chemistry, Types and Characteristics of Corundum Corundum is crystalline aluminum oxide, Al2O3, and also known as alumina. Al2O3 is also the active element in the natural abrasive material emery [LEWI76, p. 9] and in the gemstones sapphire and ruby. Aluminum oxide occurs in at least five modifications, a-Al2O3, P-Al2O3, y-Al2O3, 5-Al2O3, and e-Al2O3. The […]
Artificial Synthesis of Diamonds
2.3.3.1 Monocrystalline Diamonds The first artificial diamond synthesis was conducted by the Swedish company ASEA with a six-anvil press in February 1953 [TOLA68, WEDL77]. In 1955, company GE followed with the synthesis in a belt press and in 1958 company De Beers [MARI04]. Graphite can be transformed to diamond directly at temperatures above 1800 K […]
Methods for Grit Selection and Analysis
2.8.3 Grit Size Selection 2.8.3.1 Sieving The size distribution of abrasive grits is adjusted by sieving for coarser grits and sedimentation for finer grits [KLOC05a, p. 27, MARI07]. Sieving is the simplest method to separate particles and works with sieves of defined mesh sizes [SALM07, p. 132]. Sieving can be performed manually or automatically on […]
Phenolic Resin
Phenolic resin bonds, in particular phenol-formaldehyde resin bonds, are the most common resin bonds; tools made of this bonding type represent the largest market segment for conventional wheels after vitrified tools [KREB06, KLOC05a, p. 65, MARI07, p. 119]. Originally, this bond type was known as bakelite and for this Furfural Fig. 3.3 Structures of phenol, […]
Performance of Metallic Multi-layered Bonds
Metallic bonds provide high grit retention and low wear during grinding. However, a copper bonding might smear during grinding. Metallic bonds might have low porosity, so that fillers in the bond are added for lubrication during grinding. Metallic bonded tools are difficult to condition mechanically [WEGE11]. Electro physical and electro chemical processes can be applied […]
Abrasive Grits
The single crystal grits used in coated abrasives are similar to the ones used in grinding wheels. Grit sizes are usually graded in larger intervals than for grinding wheels [BORK92, p. 46]. The grits are fully embedded in the bond material, which leads to high resistance against grit-breakout [KONI86, KLOC09, p. 217]. Therefore, the wear […]