Migiwata Metric M35 Cobalt Steel Extremely Heat Resistant Twist Drill Bits with Straight Shank Set of 13pcs to Cut Through Hard Metals Such as Stainless Steel and Cast Iron

Different types of drill bits are used to cut holes in different types of materials. This set of Migiwata M35 cobalt steel drill bits are particularly successful in cutting through hard metals such as stainless steel and cast iron, although they can be used for softer materials, too. Cobalt drill bits are not made of pure cobalt, but rather a steel alloy with certain percent cobalt. The 5-percent alloy is known as M35 grade.The cobalt increases the strength of the steel and makes it more heat-resistant; this is an important factor in drilling hard materials because the friction of metal against metal can produce high temperatures that damage the material or the drill bit. Tests shows that the M35 cobalt steel drill bits can penetrate a 5mm-thick 304 stainless steel plate in 5 seconds. Cobalt drill bits are more expensive than other drill bits, but if you regularly drill through metal, they are a good investment since they tend to last longer. Notice: The working life of the drill bits can be largely prolonged by using with cooling liquid. The bits are not suitable for hardened steel. Specifications: Material: M35 Cobalt Steel(5% Cobalt and 95% High Speed Steel) Angle Point: 135 Degree Flute Type: spiral Hardness: Rockwell 67 Shank Type: straight shank You will get: 1.5 mm Twist Drill Bit x 1pc 2 mm Twist Drill Bit x 1pc 2.5 mm Twist Drill Bit x 1pc 3 mm Twist Drill Bit x 1pc 3.2 mm Twist Drill Bit x 1pc 3.5mm Twist Drill Bit x 1pc 4 mm Twist Drill Bit x 1pc 4.5 mm Twist Drill Bit x 1pc 4.8 mm Twist Drill Bit x 1pc 5 mm Twist Drill Bit x 1pc 5.5 mm Twist Drill Bit x 1pc 6 mm Twist Drill Bit x 1pc 6.5 mm Twist Drill Bit x 1pc Reusable Plastic Case x 1pcWarranty : Within 90 days product quality is not completely satisfied, please CONTACT US, 100% refund.