Type of metal bond grinding wheel
According to the manufacturing method, metal bond grinding wheels can be divided into: sintered metal bond grinding wheels, electroplated metal bond grinding wheels, and single-layer brazing metal bond grinding wheels.
Sintered metal bond grinding wheels are commonly used, and electroplated metal bond grinding wheels can only be used in situations where the grinding load is small. Single-layer brazing metal bond grinding wheels are a new type of metal bond grinding wheel under research and development.
Sintered metal bond grinding wheel
Sintered metal bond grinding wheels mostly use metals such as bronze and cast iron as the bond, and are manufactured by high-temperature sintering. They have high bonding strength, good formability, high temperature resistance, good thermal conductivity and wear resistance, long service life, and can withstand relatively
Traditional sintered metal bond grinding wheels have problems such as uneven distribution of abrasive particles. Wang Chunhua et al. sintered SiC abrasive metal bond abrasives prepared by direct mixing method and wrapping method, and SiC particles are more uniformly dispersed.
Xiao Bing of Nanjing University of Aeronautics and Astronautics, in view of the uneven distribution of abrasive grains, low efficiency, and easy burns of the bond and diamond caused by the current mechanical mixing of metal bond diamond abrasive tools, conducted a multi-layered abrasive uniform distribution technology.
In order to avoid the oxidation of the diamond or other damage to the diamond when the metal bond diamond grinding wheel is sintered, as well as the reduction of the bonding performance of the diamond grit and the bond, Ihara has developed a metal layer to coat the diamond grit and more
The abrasive grains coated with the metal layer are bonded together to form a diamond grinding wheel structure of agglomerates.
Plating metal bond grinding wheel
Electroplated diamond grinding wheels usually use nickel or nickel alloy as the coating metal.
Due to its high precision, electroplated grinding wheels are widely used in high-speed, ultra-high-speed grinding and precision grinding.
In order to simplify the manufacturing method of electroplated diamond grinding wheels and adjust the concentration of diamond abrasive grains on the working surface of the grinding wheel, the invention proposes that the thickness of the metal bond is less than 1/2 of the height of the diamond abrasive grains, and the size of the filler used is 1.5 to the size of the diamond abrasive grains.
Yu Aibing and others conducted research on the ultrasonic electroplating diamond grinding wheel electroplating process test, abrasive grain density test, etc., in order to obtain a reasonable ultrasonic electroplating process and improve the performance of electroplated diamond tools.
Metal bond additive element
In order to enhance the holding force of the bond to abrasive grains, as well as the bond strength, grinding performance, mechanical properties, and life of the grinding wheel, strong carbide forming elements, rare earth elements and other elements can be added to the metal bond.
Studies have shown that the addition of rare earth elements La and Ce can improve the bonding force between diamond and matrix, the mechanical properties of the matrix, the height of the diamond edge, and the self-sharpening of diamond tools.
In order to meet the performance requirements of metal bond grinding wheels, Luciano et al. proposed to add Si(
Metal bond grinding wheel dressing
The dressing technology of metal bond grinding wheels has always been the focus of its research.
Scholars from various countries are competing to develop new dressing technologies for metal-based diamond grinding wheels. The main dressing methods are as follows:
Contact discharge dressing method (Electro-contactdischargedressing, ECDD)
Electro-contact discharge dressing (ECDD) was first proposed by Tamaki and Kondoh in 1999.
It uses the metal bond of the grinding wheel to contact the metal chips to form a current loop, generate instantaneous discharge, and erode the metal bond at local high temperatures to achieve the purpose of dressing the grinding wheel.
Xie Jin of South China University of Technology and Tamaki of Kitami Institute of Technology in Japan used the contact discharge dressing method to sharpen the 600# diamond grinding wheel. After grinding the optical glass (BK10), the Ra reached 0.12μm.
Xie Jin and Tamaki conducted a series of experimental studies on the electrolyte of the contact discharge dressing technology. The experimental results proved that the electrolyte largely determines the performance of the contact discharge dressing technology.
In-gas EDM method
The gas-in-gas EDM method was first proposed by Kunieda and Yoshida in Japan in 1997. It uses a high-speed air flow jetted from a tubular tool electrode to remove vaporized and melted workpiece materials, and at the same time replaces the working fluid to compress the discharge channel restriction
Its expansion effect makes the discharge energy highly concentrated in a very small area to achieve the purpose of removing the binding agent.
Xie Jin and others from South China University of Technology used single-pulse electric spark discharge in gas to achieve the sharpening of the metal bond precision diamond grinding wheel, which produced a better edge morphology of the grinding wheel and improved the grinding surface quality.
Ultrasonic vibration trimming method
The ultrasonic vibration dressing method is proposed by the scholars of the Bulgarian Institute of Technology. It uses the energy of ultrasonic to drive the end face of the tool to ultrasonic vibration, forcing the abrasive particles in the mixed oil abrasive to continuously impact and polish the processed surface at a large speed and acceleration.
The material in the processing area is crushed into very fine particles, which are blown down from the material.
Based on the principle of ultrasonic elliptical vibration driven by a single longitudinal vibration source, Gao Guofu and others used elliptical ultrasonic-assisted mechanical dressing technology to carry out technical research on the rapid and precise dressing of metal bond diamond grinding wheels, selecting reasonable dressing parameters, and achieving fine particle size
Low-cost and fast dressing of diamond wheels.
Zhao Bo and others are right
Research on the influencing factors of the new elliptical ultrasonic vibration trimming technology, experimental research proves that the trimming force of the elliptical ultrasonic vibration trimming technology is small, and it decreases with the increase of the ultrasonic vibration power.