Magnetic abrasive finishing was first mentioned by Coats in a patent filed in 1938 [COAT40, SINL10]. It is a finishing method for flat, cylindrical, and ball grinding and especially suited for hard to machine materials [SINL10]. The magnetic abrasive particles can be produced by sintering, adhesive based processes, plasma based process (powder melting or plasma […]
Рубрика: Life Cycle and Sustainability of Abrasive Tools
Chemistry, Types of Diamond and Performance
Carbon forms several allotropes: hexagonal graphite, diamond in the cubic zinc blende structure, non-graphitic carbon, and the cage-like fullerene (C60), discovered in 1985 [JAEG10]. Diamond is the hardest material in nature and very resistant against compaction. This is due to the dense packing of the carbon atoms, their regular, symmetrical order, and the energy rich […]
Grit Size
2.8.1.1 Effect on Tool Performance In bonded abrasive tools, grit size in combination with grit concentration influences the number of cutting edges (Sect. 6.2 “Cutting Edge Density”). As consequence, the undeformed chip thickness during grinding is affected [WERN71]. Grinding tools with smaller grit sizes commonly cause higher machining forces and shorter tool life. [LINK15] Grit […]
Social Dimension
Mining for raw materials is known for having many physical, chemical, biological, ergonomic and psychosocial occupational health hazards [DONO04]. In addition, the processing of grits can be harmful to workers. For example, the emissions from melting corundum from bauxite in electric arc furnaces can lead to a lung disease known as corundum smelters lung, bauxite […]
Performance/Grit Retention
The first vitrified bonded wheels were considered as inappropriate for large temperature variations because the bond was not elastic enough to withstand thermal expansion differences within the tool [KING86, p. 87]. Certain bond elasticity is important to equalize the volumetric expansion of the abrasive grits induced by the grinding process heat [STAD62, p. 51]. Vitrified […]
Tool Grinding Wheels
Tool steels and high-speed steels are machined with corundum or CBN wheels [LINK09, KONI80]. Carbides and ceramic tools are ground mainly with silicon carbide or diamond wheels. Diamond grit sizes for carbide tool grinding wheels lie commonly between D46 and D181 [FRIE02, p. 46]. Diamond grits with low toughness enable self-sharpening during the grinding process, […]
Single Layer Plated Tools
Electroplated diamond grinding tools exhibit potential for recycling. In particular, the body can be reused. Electroplated grinding wheels are generally returned to the manufacturer, who will strip off the abrasive layer and re-plate the body. Usually chemical and electrochemical stripping methods are used [BULJ99]. Chemical methods such as acid baths corrode the bonding [BULJ99, YU11]. […]
Hardness Testing by Grit Breakout Test or Scratch Test
Merbecks developed the grit breakout test and scratch test following ideas from Opitz and Peklenik [MERB03, PEKL60]. These tests are well applicable to superabrasive grinding tools as they do not damage the abrasive layer, leave holes, or measure the whole body elasticity [KLOC05c, MERB03]. In the single grit breakout test, a cemented carbide tip is […]
G-Ratio
Tool life between conditioning is measured in time, per number of machined workpieces or workpiece volume removal [PAUC08, p. 343]. The G-ratio is a common parameter for describing the tool lifespan as ratio of machined workpiece volume, Vw, and worn grinding tool volume, Vs (Eq. 6.20) [MALK08]. The G-ratio depends on the machined material, tool […]
Life Cycle Engineering
Companies have to find ways to capture and measure their sustainability performance. The overall goal of sustainability encompasses the three dimensions of economic, environmental and social sustainability [HAUS05]. Life Cycle Costing (LCC), Life Cycle Assessment (LCA), and Social Life Cycle Assessment (SLCA) are methods to assess each dimension. Sustainability indicators evaluate the overall performance in […]