Superabrasive grinding wheels made of diamond powder or cubic boron nitride (CBN) have been widely used in various aspects of the grinding field because of their excellent grinding performance. The diamond grinding wheel is a high-performance tool for grinding hard alloy, glass, ceramics, gems and other high-hard and brittle materials. In recent years, with the rapid development of high-speed grinding and ultra-precision grinding technology, higher requirements have been placed on diamond grinding wheels. Ceramic and resin bonded diamond grinding wheels can no longer meet the needs of production. Metal bond diamond grinding wheels have been widely used in production due to their remarkable characteristics such as high bonding strength, good formability and long service life.

According to the different metal elements and alloy composition of metal binding agent, it can be divided into copper base, cobalt base, iron base, titanium base and so on. Transitional elements are the most widely used metal binder types.

Copper-Base Binder in Diamond Tools

The copper-based binder with Cu as the main component is the earliest researched binder type, which has the characteristics of good toughness, moderate strength and low sintering temperature. The research shows that in the copper-based binder, the two factors that determine the self-sharpening of the abrasive tool are the addition of alloying elements to improve the mechanical properties of the matrix and the interface bonding between Cu and diamond.

Commonly used copper-based binders include Cu-Fe-Co, Cu-Sn, Cu-Sn-Ti, Cu-Sn-Pb, Cu-Al-Mg and other systems.

Due to the characteristics of the electronic structure of the copper atoms, the bond strength of the copper-based bond and diamond cannot reach a very high degree. However, the emergence of cobalt-based binders made up for the lack of copper-based binders that do not hold diamond grains firmly.

Cobalt-Based Binder in Diamond Tools

Cobalt-based binders are widely used in sintered diamond abrasive tools. Cobalt-based binders have the characteristics of high hardness, good strength toughness, good chemical compatibility, low sintering temperature, and excellent wear performance. In cobalt-containing metal bond diamond abrasive tools, cobalt plays a very important role. It can moderately reduce the wear resistance of the bonding agent, so that the diamond grits can maintain a large edge height and ensure the sharpness of the abrasive tool. Usually, cobalt-based binders are mainly used in the fields of geology, rock drill bits and other fields that require high performance of abrasive tools. However, since cobalt is expensive and toxic, it is not suitable as the main component of metal binders from the perspective of cost-saving and environmental protection. Therefore, many engineers are currently working on the preparation of high-performance low-cobalt or even cobalt-free bond abrasives.

Iron-Based Binder in Dimond Tools

Iron-based binders are a potential alternative to cobalt-based binders. There are many types of iron powder used in iron-based binders, including reduced iron powder with simple production process and carbonyl iron powder mostly used in the manufacture of high-performance abrasives. The formation of iron alloys with other metals can greatly improve the performance of the carcass, even comparable to cobalt-based binders. Commonly used iron-based binder systems include Fe-Cu-Sn, Fe-Co-Ni, etc. The performance of iron-based binder is sensitive to the sintering temperature, which can easily cause under-burning or over-burning and erode diamond particles.

Due to the relatively large solubility of Cu in austenite, iron is easy to etch diamond grits during sintering, resulting in the influence of the sintering process on the performance of the binder matrix and many other factors that limit the application of iron-based binders.

Metal binder in diamond tools have excellent performance and wide application prospects, Crownky Superabrasive provides quality assurance and customizable synthetic diamond powder for metal bond diamond tools.