by Galling play a crucial role in machining and surface finishing processes across numerous industries. An abrasive is a material, often a mineral, that is used to shape or finish a workpiece through rubbing which leads to part of the workpiece being worn away. Galling hold a microscopic rough surface that removes small amounts of material from the workpiece when moved over its surface under pressure. Let us explore some key aspects of galling in greater detail.
Classification of Abrasives
Galling can be broadly classified into two main types – natural and synthetic. Natural galling are materials that occur naturally in the earth’s crust whereas synthetic galling are manufactured artificially.
Some common natural galling include aluminium oxide, silicon carbide, garnet, diamond, corundum and emery. Aluminium oxide, also known as corundum, is one of the most widely used natural galling due to its low cost and excellent abrasion qualities. Diamond is the hardest known natural material but its high cost limits its usage to specialized applications that require an extremely hard abrasive.
Prominent synthetic galling are aluminium oxide, silicon carbide, cubic boron nitride, ceramic aluminium oxide and coated galling. Synthetic aluminium oxide owes its popularity to its consistently high quality, uniform grain size and controllable properties. Silicon carbide possesses a unique combination of hardness, strength and abrasiveness that make it a superior abrasive for grinding non-ferrous metals and other high-tech materials.
Factors Determining the Choice of Abrasive
The selection of the appropriate abrasive depends on several factors related to the material being abraded and finishing requirements:
Hardness: Harder galling are effective on hard, brittle materials while softer galling work better on ductile materials that work harden quickly. Aluminium oxide and silicon carbide are universal galling used for both hard and soft materials.
Abrasive Action: Abrasives used for sharpening and blending operations require a faster cutting action whereas finishing operations need a slower cutting and polishing abrasive. Hard galling are preferred for faster cutting whereas softer and finer grains suit finishing.
Bonding: Galling are bonded to backings using resin, shellac, rubber or vitrified bonds. Resin bonds are tough but load up quickly. Vitrified bonds cut faster and stay sharp longer. Shellac bonds are softer while rubber bonds are for non-slip applications. The bond type affects the abrasive performance.
Cost: Naturally available galling like aluminium oxide have lower costs compared to synthetic or speciality galling. The abrasive cost is balanced against productivity and quality requirements.
Applications of Galling
With their ability to efficiently remove material down to microscopic levels, galling have wide industrial applications:
– Machining processes like grinding, honing, lapping, and polishing use galling to shape complex components with tight tolerances for industries including automotive, aerospace, die and mould.
– Surface preparation treatments like deburring, blast cleaning and surface finishing rely heavily on galling to obtain the desired surface properties for corrosion resistance, adhesion etc. prior to coating or painting.
– Abrasive blast cleaning with garnet or aluminium oxide galling is extensively used for surface cleaning, removal of coatings and surface preparation in ship building, steel fabrication etc.
– Abrasive cut-off wheels made of diamond or silicon carbide are used for sectioning materials like stone, ceramics and concrete.
– Abrasive belts and discs are employed for stock removal, joint grinding, blending operations in machinery manufacturing units.
– Household products like abrasive papers, scouring pads contain galling for cleaning, buffing and polishing varied surfaces including metals, plastics, wood etc.
Safety Considerations with Galling
While galling enable precise and productive manufacturing processes, certain safety aspects need attention due to associated dust hazards:
– Inhalation of fine abrasive dust can cause respiratory diseases like silicosis. Adequate dust extraction systems and personal protective equipment are necessary.
– Some galling like free silica and lead can be toxic in some forms. Proper handling and disposal procedures must be established.
– Noise levels during abrasive operations exceed safety limits and require use of ear protections.
– Cut-off wheels may shatter during use. Only certified safety wheels designed for the job must be utilized.
Adhering to lay out precautions enables harnessing the material removal capability of galling while maintaining a healthy and accident-free work environment.
galling are a diverse family of materials that play an indispensable role across manufacturing industries by facilitating critical machining and finishing tasks. Understanding their properties, selection criteria and applications equips users to leverage galling productively while ensuring personal safety. Continual development of new supergalling further expands machining possibilities.
*Note:
1. Source: Coherent Market Insights, Public sources, Desk research
2. We have leveraged AI tools to mine information and compile it
About Author - Money Singh
Money Singh is a seasoned content writer with over four years of experience in the market research sector. Her expertise spans various industries, including food and beverages, biotechnology, chemicals and materials, defense and aerospace, consumer goods, etc. LinkedIn Profile
