Is it too difficult to drill stainless steel? What kind of drill bit is the best for processing stainless steel?
High speed steel drill bit
High-speed steel (HSS) is a tool steel with high hardness, high wear resistance and high heat resistance, also known as high-speed tool steel or front steel, commonly known as white steel. High-speed steel knives are tougher and easier to cut than ordinary knives.
Titanium-plated drill bits are also high-speed steel titanium-plated. Titanium-plated steel drill bits: extremely high hardness (hardness can reach HRC78, provided that the real industrial plating is required, not the decorative plating)
1. The hardness of high-speed steel is between HRC51-55, and the workpiece cannot be drilled after the hardness reaches HRC35. After titanium plating, the hardness of the drill bit can reach about HRC68, and the workpiece can be drilled to HRC48;
2. After the drill bit is plated with titanium, the wear resistance and high temperature resistance are significantly improved, which increases the life of the drill bit
3. After the drill bit is plated with titanium, the color is like gold and the appearance is beautiful
4. After the drill bit is plated with titanium, the factory can increase the price a lot and increase the profit of the factory
5. The titanium-plated drill bit can reduce the red hotness of the drill bit and increase the drilling progress of the drill bit
However: more than 95% of titanium-plated drill bits on the market are fake, because most of the propaganda titanium-plated drill bits are only decorative plating, just to achieve the effect of the color of the titanium-plated drill bit for aesthetics, so in the industry, in order to distinguish between these two kinds of titanium plating, fake It's called decorative plating, it's really called industrial plating.
Carbide drill bit
High-speed steel has better toughness, strength and heat resistance than carbon tool steel, and its cutting speed is much higher than that of carbon tool steel (iron-carbon alloy), hence the name high-speed steel; and cemented carbide has better performance than high-speed steel Even better, the cutting speed can be increased by 2-3 times.
High-speed steel drill bits are also alloy drill bits! General tool steel also belongs to alloy steel, but it is only iron-carbon alloy. High-speed steel is also divided into ordinary high-speed steel and high-quality high-speed steel. Therefore, alloy drill bits generally refer to carbide drill bits. High-speed steel drills can maintain high hardness even when high heat is generated by high-speed cutting (about 500°C), and the HRC can be above 60. Cemented carbide drill bits (usually made of tungsten steel) have a series of excellent properties such as high hardness, wear resistance, good strength and toughness, heat resistance and corrosion resistance, especially its high hardness and wear resistance, even at 500 ℃ The temperature remains basically unchanged, and the hardness is still high at 1000°C.
Cobalt-containing drill bits are drill bits that contain the chemical element cobalt Co. Generally, cobalt is added to the raw material of high-speed steel. The purpose of adding cobalt is to improve the high temperature resistance and abrasive resistance of the drill bit, so that the drilling can achieve the purpose. In practice, it is generally used to process stainless steel, copper, and aluminum products. These products have high strength characteristics, that is, poor plasticity. During the drilling process of these materials, the discharged cuttings are attached to the drill bit. In order to solve this problem, later generations invented the cobalt-containing drill bit. When the ordinary drill bit encounters high temperature, it expands rapidly, and the continuous torque applied by the drill shank causes the drill bit itself Broken, or the drill tip can not be used; in a word, cobalt-containing drills are added with the chemical element cobalt, which is used to cut high-speed steel that is highly abrasive and prone to produce high-temperature metals.
What kind of drill bit is used to process stainless steel?
Stainless steel is characterized by high toughness and easy sticking to the knife. Therefore, the hardness of the drill bit is required to be high, and the surface finish is good. The top angle of the drill bit is larger than that of the ordinary drill bit (between 130-135 degrees). At the same time, the cooling should be sufficient. And the feed amount is greater than 0.15mm so as not to cut the hardened layer of cold work as much as possible. The cutting speed is as low as possible to reduce the cutting temperature. The cutting fluid adopts thick emulsion. Commonly used drills for processing stainless steel are: high-cobalt drills (m35 drills, m42 drills), among which m42 drills are the most cost-effective. In addition, carbide drill bits can be used, but the price is higher.