Digital currency HRC
T in steel T10 (T10 carbon tool steel) means carbon tool steel (high carbon)
The strength and wear resistance ofT10 carbon tool steel are higher than those of T8 and T9, but the hot hardness is low, the hardenability is not high, the quenching deformation is large, the grain size is fine, it is not easy to overheat ring quenching, and the fine grain structure can still be maintained
After quenching, there are undissolved carbides in the steel, so the wear resistance is high. It is used to make tools with sharp edge and a little toughness. Suitable for manufacturing, poor cutting conditions All kinds of tools with high toughness and sharp edge are also used as wear-resistant parts Mechanical properties and hardness: annealed, ≤ 197hb, indentation diameter ≥ 4.30mm; Quenching, ≥ 62Hrc heat treatment specification: sample quenching 760 ~ 780 ℃, water coolingquenching T10 steel, recommended quenching specification is shown in table 2-22-7, cold treatment is shown in table 2-22-8, quenching related curve is shown in Fig. 2-22-7 ~ Fig. 2-22-13
The physical properties ofT10 steel are shown in Table 1-1 and table 1-2; Permeability μ 88 MH / m; The coercivity HC is 477.48 ~ 1273.18a/m (the lower limit of HC is suitable for spheroidized structure, and the upper limit is suitable for pearlite structure); The saturation magnetic inction BS is 1.93 ~ 1.97t
the die cavity of cold heading die made of this steel is deep and steep, early collapse failure often occurs in use, and the service life of the punch is less than 4000 times. It is analyzed that the reason is that the feed rate of cavity grinding is too large and the burn is softened. After the improvement of grinding process, the service life of light punch is significantly increased, and it is stable at more than 30000 times
when the steel is used to make cold punching die, the tool can punch about 30000 times for each grinding; When the same thickness of black iron sheet (hot rolled steel plate) is used, the service life will be reced to about 17000 times. Although there is no oxide scale on the surface of semi hot rolled plate, there is a "hard shell", which will seriously rece the service life of the die
1. Carbon tool steel: the carbon content of carbon tool steel is high, ranging from 0.65% to 1.35%, which belongs to hypoeutectoid, eutectoid or hypereutectoid steel according to its microstructure. After heat treatment, the surface of carbon tool steel has higher hardness and wear resistance, and the core has better toughness; The annealed hardness is low (no more than hb207), and the machinability is good. But its red hardness is poor. When the working temperature reaches 250 ℃, the hardness and wear resistance of the steel decrease sharply, and the hardness drops below HRC60. The hardenability of this kind of steel is low. The larger tools can not be hardened (the diameter of water hardened is 15mm), and the hardness of the surface hardened layer and the central part is very different. The tool is easy to deform ring quenching. In addition, the quenching temperature range is narrow, so the quenching temperature should be strictly controlled. Prevent overheating, decarburization and deformation
2, T7, t7a hypoeutectoid steel: it has good plasticity, toughness, strength and certain hardness, can withstand vibration and impact load, but poor cutting ability. It is used to manufacture tools that bear little impact load and require appropriate hardness, wear resistance and good toughness, such as forging dies, chisels, hammers, punches, metal shears, reaming drills, steel seals, woodworking tools, pneumatic tools, machine tool tips, fitter tools, drilling tools, blunt surgical and medical appliances, etc
3, T8, T8A eutectoid steel: it is easy to overheat ring quenching and heating, and has large deformation, low plasticity and strength, so it is not suitable to make tools that bear greater impact, but it has higher hardness and wear resistance after heat treatment. It is used to manufacture cutting edge tools that keep constant heat when working, such as woodworking tools, pneumatic tools, locksmith tools, simple molds, rivet dies, center hole blunders and dies, steel cutting tools, bearings, cutting tools, aluminum tin alloy die-casting plates and cores, and all kinds of springs
4, t8mn, t8mna eutectoid steel: it has higher hardenability and hardness, but lower plasticity and strength. It is used to manufacture woodworking tools, hand saw blades, engraving tools, rivet dies, spring, band saw blades, circular saw blades, chisels for coal mine, chisels for stonework, etc
5, T9, T9A hypereutectoid Steels: have higher hardness, but lower plasticity and strength. It is used to manufacture tools with high hardness and toughness, such as engraving tools, rivet dies, press dies, punches, woodworking tools, cutting parts of agricultural machinery, rock drilling tools and split pin of casting dies
6, T10, T10A hypereutectoid steel: the grain size is fine, and it will not overheat ring quenching (up to 800 ℃), and the fine grain structure can still be maintained; There are undissolved carbides in quenched steel, so it has higher wear resistance but lower toughness than T8 and T8A steel
it is used to make tools whose cutting edge is not heated when working, and has sharp edge and a little toughness without bearing impact load, such as wood processing tools, hand cross saw, hand fine wood tools, machine fine wood tools, twist drills, wire drawing dies, stamping dies, cold heading dies, screwdrivers, reaming tools, thread rolling boards, turning tools, planers, milling cutters, currency dies, etc Cold trimming and piercing die with small size and uniform cross section, low precision and simple shape card board, fitter scraper, hard rock drill, rivet and nail making tools, screwdrivers, files, chisels for engraving, paper cutting and tobacco cutting tools, etc
7, T11 and t11a hypereutectoid Steels: they have better comprehensive mechanical properties (such as hardness, wear resistance and toughness), finer grains and less sensitivity to grain growth and carbide network formation ring heating. It is used to manufacture tools with constant cutting edge heat ring working, such as saw, chisel, tap, file, scraper, spring, instrument, reamer, die, tobacco cutting tool, cold stamping die and woodworking tool with small size and no sharp change in section, etc. T12, T12A hypereutectoid steel. Because of the high carbon content. After quenching, there are still more excess carbides, so the hardness and wear resistance are high, but the toughness is low, and the quenching deformation is large. It is not suitable for manufacturing tools with high cutting speed and impact load. It is used to manufacture tools that are not subject to impact load, cutting speed is not high, and cutting edge is not hot, such as turning tool, milling cutter, drill, reamer, reamer, tap, die, scraper, gauge, blade, small punch, steel file, saw, spring, tobacco cutting tool, and cold trimming die and punching die with small section size
it is used to manufacture metal cutting tools that are not subject to impact load but require very high hardness, such as razor, scraper, wire drawing tool, file, engraving tool, drill, hard rock processing tool and engraving tool, etc.