How to identify the True and False Tool Steel Cr12
Cr12 is one of the representative cold work tool steels, belonging to the steel of high-carbon and high chromium. In order to obtain larger profits, some undesirable factories manufacture the fakes by various kinds of ways, which has caused a large economic loss to customers.
Specifications
1. Cr12 is a kind of cold work tool in widespread use.
2. With high strength, good harden-ability and good abrasion resistance.
3. Without good impact toughness.
4. Commonly used for manufacturing cold work molds of excellent abrasion resistance as well as punch heads, cold cutting scissors, drill bushes, gauges, wire drawing dies, stamping dies, wire drawing plates, drawing dies, thread rolling dies, etc.
Applications
1. The thin plate with the thickness less than 2mm, blanking die, punching die and stamping mould.
2. All kinds of scissors, insert blade,woodworking blade.
3. Thread rolling die and abrasion resistant slide block.
4. Cold-heading die and thermosetting resin molding die.
5. Deep-drawing moulds and cold-extruding dies.
Ways of Making Fakes
The first way of making fakes is to reduce the effective chemical compositions of steel, such as chromium and carbon, so as to reduce the cost, for example replacing Cr12 with Cr8.
The second way is changing the manufacture process to reduce the cost. Some manufactures smelt steel with Intermediate frequency furnace instead of electric furnace, which leads to the high inclusion, some use continuous casting instead of forging, some use ordinary tempering instead of spheroidizing annealing, others reduce the rolling ratio. As a result, it is impossible to meet the costumers’ requirements. What’s worse, both the safety of manufacturing process and the quality of finished molds can’t be guaranteed, so the service life of these molds is greatly shortened.
1. Recognize from the chemical compositions: carbon, chromium are unable to meet the national standard requirements. The real Cr12 contains more than 11.5% chromium and 2.0% carbon.
2. Recognize from its properties: abrasion resistance, carbide level and hardness after quenching（＜58HCR）are unable to meet the national standard requirements.
3. Recognize from the price: The price of Cr12 light board is above RMB 16 per kilogram in traditional sales, but generally at the price between RMB18 and RMB20 per kilogram.
