Carbide Tools: History, Classification & Advantages
Carbide Tools and Inserts are the most widely used tools in the Machining Industry for the last few decades. But have you ever wondered What is Carbide and why have Carbide Tools become so popular.
Carbide is a Chemical Compound composed of Carbon along with a less electronegative element than Carbon itself. Carbides can be broadly classified into:
- Metal Carbides: Carbon compounded with less electronegative metals like Tungsten, Titanium, Cobalt, Tantalum, or Vanadium
- Non-Metal Carbides: Carbon compounded with less electronegative non-metals like Boron, Calcium, or Silicon
Due to their extreme hardness & resistance to high temperatures, Metal Carbides are used in cutting, drilling, grinding, abrasives and polishing tools.
Tungsten Carbide, commonly known as Carbide these days, a compound of Carbon and Tungsten has revolutionized the Machine Tool Industry over the last decades by providing increased cutting speed and feed rate with a longer tool life span as compared to their traditional counterparts.
A Scientist from the General Electric Company’s Lamp Department named Dr. Samuel Leslie Hoyt was the first to investigate Tungsten Carbide as a Cutting Tool Material. Later Dr. Samuel Leslie Hoyt went on to develop Carboloy, an alloy of Tungsten, Carbide and Cobalt.
Advantages of Carbide Tools
- Carbide tools can be worked at higher speeds as compared to HSS tools, approximately 6 to 8 times higher speeds.
- Young’s Modulus of Elasticity of Carbide tools is 3 times that of steel, making it stiff.
- Workpiece/parts machines using Carbide tools generate a surface finish of high quality.
- Carbide Tools have an exceptional resistance to abrasion.
- They have a high resistance to Catering and Thermal Deformations.
- Carbide tools have a high wear resistance, enabling the user to use the tool at higher speeds and longer durations as compared to other materials like HSS.
- Carbide tools provide a higher value for money than their steel counterparts.
- Carbide tools can machine Hardened Steel.
- Carbide tools are chemically inert.
- Torsional Strength of Carbide Tools is twice of that of HSS tools.
- Tips of Carbide Tipped tools can be easily replaced for further use.
Classification of Carbide Tools
Carbide Tools are classified into three major grades:
- WEAR Grade: Primarily used in dies, machine and tool guides as well as in everyday items like fishing rods, reels and wherever good wear resistance is required.
- IMPACT Grade: Particularly used in the processes of Forming and Stamping, heads of mining drills and also dies.
- CUTTING TOOL Grade: Tool grades of cemented carbides are further classified into two parts based on their primary application, Cast Iron Carbide and Steel Grade Carbide. Cast Iron Carbides are used on cast iron which is a non-ductile material, whereas Steel Grade Carbides are used to cut a ductile material of steel. Cast Iron Carbides are more resistant to abrasion wear. Steel Grade Carbides require more resistance to cratering and heat.