Definition of grinding
What is grinding? Grinding can be described as an operation to minimize the roughness of the surface of a workpiece without damaging its shape. Grinding is a kind of machining action using a grinder. The Chinese word for grinding machine is called a grinding disk in Japan, and some people call it a lapping disk. Optical grinding operation is mainly divided into fine grinding and polishing, optical books refer to fine grinding as sanding, but there are also books that classify sanding as polishing in the broad sense. In order to minimize the surface roughness of the workpiece, filing, grinding stones, sandpaper, buffing wheels, disk grinders, etc. can be used.
Grinding method
There are various methods for grinding operations, from deburring to polishing. About 30 years ago, ultra-precision machining became practical for the production of multifaceted mirrors or aspherical surfaces. Products cut with diamond cutters have extremely high shape accuracy and low surface roughness, and do not require grinding.
The following grinding methods are available.
(1)Deburring by heating, roller grinding, magnetic grinding, shot blasting, polishing, and burring wheels.
(2)Rough grinding with disc sanders and belt sanders
(3)Use of abrasives as media
(4) Fine grinding with an abrasive belt
(5) Grinding stone polishing, including manual and automatic polishing, rotary and surface grinding machines
(6) Polishing Machine
(7) Manual operation grinding
Utilization of Grinding
The purpose of grinding varies from workpiece to workpiece.
(2)CDs are ground on the inside of the embosser for a more uniform thickness; reduced roughness on the inside and fewer signal errors on the formed disk surface.
(3)Lenses and mirrors are used to grind products for their own optical function, sometimes to study materials, to observe structures with a microscope, and to find out the depth of the processed metamorphic layer.
Grinding 5 Roles
Grinding improves the surface finish of the workpiece to meet the requirements of production and application.
(1)Chipping damage (lots of tiny abrasive action)
(2)Extrusion (internal deformation or fiber layer slippage near the surface of the base material caused by polishing tools)
(3)Melting (metals sometimes reach very high temperatures in a small area)
(4)Recombination (especially significant when grinding metals, forcing small atoms or molecules to bond)
(5)Formation of machined metamorphic layers (formation of abrasive surfaces due to plastic flow)
The right way to grind
The abrasive should be discontinuous, the abrasive of Aluminum Oxide or diamond for grinding are all small hard grains to contact the workpiece discontinuously; the abrasive should escape, the abrasive is used in a short distance, and when the force applied is too large, the abrasive should escape to the inside of the polishing tool, to prevent the workpiece from causing big scars.
When grinding, friction overheat will cause the workpiece to melt or distortion of shape, need to use water-based or oil-based lubricant lubrication, can cool, dispersion of abrasive, exclude grinding chips, can buffer the role of grinding.
What is an abrasive?
What is abrasive? Abrasive is aluminum oxide, silicon carbide, diamond, cerium oxide, red ochre, CBN and other powder or abrasive molding grinding materials, including aluminum oxide powder, diamond powder, grinding wheel, etc., the abrasive material in the grinding process and then chipped or worn into smaller abrasive material, which in the workpiece grinding into a mirror for the very important nature of abrasive material needs to be hard, but easy to chipped, small and convex, the same shape and size, and does not react with the workpiece as a good.
The difference between general molds and precision molds lies in the requirements for precision. The precision of general molds such as stationery, electrical machinery housings, etc. is plus or minus 0.1~0.05mm, and the base surface is relatively rough; the precision of smaller precision molds such as optical components or gears, connectors, etc. is plus or minus 0.05~0.01mm, and the roughness of the surface and the precision of the shape are more stringent.
Characteristics of each processed
(1)Cutting surfaces, inevitable pick-feed marks, roughness is greater, grinding may occur undulation, less microcracks
(2)The grinding surface, with high processing precision, is likely to have microcracks, and when a glossy surface is required, the grinding surface will be fine-tuned.
(3) EDM surfaces are susceptible to work-hardening and softening, making it difficult to achieve tight shape accuracy.
(4)High-precision machining of flat surfaces, spherical surfaces, round holes, tapered holes, etc., by precision machining.
(5)Gilded surfaces, sometimes the gilded surfaces are ground directly, and sometimes the surfaces are ground with a diamond cutter that is minutely sharpened.
Micro Removal Processing
Due to some kind of external force and deformation or deterioration of the part is called the deterioration layer, cutting, grinding, heat treatment may occur in the processing stage of the deterioration layer is called the processing of the deterioration layer, grinding is not found in pinholes, orange peel in the use of the emergence of the impact of residual deterioration layer may be cutting the deterioration layer is serious in the grinding from the grinding surface of the underside of the appearance of milling cutter or lathe traces, in order to avoid the formation of the formation of machined layer of deterioration, the workpiece needs to be divided into micro-removal of the surface, the process is called micro-removal of the surface, this process is called the micro-removal of the process.
