Sintered corundum is a family of grains produced from unfused alumina by sintering processes [JACK11, p. 29]. The aim of sintering is to form a solid ceramic body of a-Al2O3 with a regular, fine-crystalline structure [KLOC05a, p. 25]. This structure is supposed to have a good wear resistance in the abrasive grinding process [KLOC05a, p. […]
Рубрика: Life Cycle and Sustainability of Abrasive Tools
Performance of CBN
In the first years of CBN at the market, it was seen as competitor to diamond. However, CBN proved soon to be an ideal complement for machining of hard to machine ferreous materials [JUCH78]. In addition, CBN has advantages in its higher thermal stability over diamond. In the beginning, CBN was bonded in metal or […]
Packing Density
Packing density or bulk density depends on grit size and shape. For example, equidimensional shapes pack to a higher bulk density than flat shapes [MENA00]. The packing density is a rather simple but effective measure for the dominant grit shape of a batch, if grit size and size distribution are known [MALK08, SCHT81]. Measurement procedures […]
Fillers in Resin Bonds
Fillers in resin bonds have several tasks in both manufacturing phase and grinding operation: They induce porosity, reinforce bond properties, change aesthetics, and more [FRAC10]. Common fillers in resin bonded grinding tools are cryolite (Na3AlF6), pyrite (FeS2), zinc sulfide (ZnS), lithopone (ZnSBaSO4), potassium fluoroborate and potassium chloride (KAlF4, K3AlF6), potassium sulphate (K2SO4), and mixtures of […]
Manufacturing of Brazed Bonds
Brazing is a soldering process at higher temperatures. The grits are held mechanically and chemically in the bond. Therefore, the grit exposure can be higher than for electroplated wheels leading to bigger chip space (Fig. 3.19) [MARI04, p. 416 f.]. Chemically bonded grits allow for even thinner bonding layers than electroplated grits [CHAT90]. This has […]
Lapping
Lapping is a mainly room-bound process with geometrically undefined cutting edges. It is defined as a cutting process with loose grits distributed in a fluid or paste, so called lapping slurry, guided by a counterpart, which is usually shape-transferring (also called lapping tool). The cutting paths of the individual grits are ideally undirected [KLOC09, p. […]
Fiber Reinforced Resin
Asen [ASEN08] has patented a wheel body made from a fiber composite, specifically with carbon fibers, glass fibers, or synthetic fibers. Different fiber structures are undergoing investigation, in particular uni-directional, orthotroph (fibers in different orthogonal directions) or transversal-isotrop [KRAF08]. The fiber structure affects body strength and isotropy. Vitrified and resin bonded abrasive layers are glued […]
Cutting Edge Density
Cutting edge density is important to understand tool performance during the grinding process. Many researchers analyzed the statistical nature of the cutting edges [KASS69, BUTT68, SALJ88, HOU03, LORT75, etc.]. 6.2.1 Definitions 6.2.1.1 Static Cutting Edge Density Researchers differentiate between grit number and cutting edge number because each grit can have several cutting edges. However, both […]
Dressing with Diamond Tools
Today, dressing tools with diamond material are commonly used for grinding wheels [KLOC05a], using either stationary or rotating dressing tools. Stationary tools move parallel along to the grinding wheel axis on a path defined via NC programming or guide ruler (Fig. 6.17). The grinding wheel topography is generated like in a turning process [KLOC05a]. The […]
Grinding Process Model
7.3.2.1 Traditional Fundamental Requirements in Grinding Manufacturing processes have to accomplish certain tasks depending on workpiece material, stock removal (finishing or roughing operation), availability of machines, batch size, form and dimension tolerances, achieved surface roughness and integrity, and more [LINK12c]. The following discussions focus on ductile material in finishing operations and the choice of the […]