(one) of requirement of contented work requirement 1. Wearability preform is in in mould antrum when plasticity is metamorphic, edge antrum surface flows to slide again already, make model the attrition with the fierce generation between antrum surface and preform, because wear away,bring about a mould thereby and invalidation. So the wearability of material is one of function with the the basiccest, mainest mould. Hardness is the main factor that affects wearability. Usually, the hardness of mould spare parts is taller, wear extent is smaller, wearability is better also. Additional, wearability returns the sort with the carbide in material, amount, configuration, size to reach distributing about. 1. The working requirement of obdurability mould mostly very abominable, some often bear bigger concussion negative charge, bring about brittleness to rupture thereby. When working to prevent mould spare parts abrupt fragile break, the mould should have higher intensity and tenacity. The tenacity of the mould basically depends on granuality of the quantity containing carbon of material, brilliant and constituent position. 2. In process of job of mould of fatigue fracture function, below the long-term effect of circular stress, often bring about fatigue fracture. Its form has small energy to pound fatigue fracture, drawing fatigue fracture to contact fatigue fracture and bend fatigue to rupture for many times. The fatigue fracture function of the mould basically depends on its intensity, tenacity, hardness, and the content of the field trash in material. 3. High temperature capability is entered higher when the working temperature of the mould, can make hardness and intensity drop, bring about a mould inchoate wear away or produce plasticity to be out of shape and invalidation. Accordingly, mould material should be had taller fight temper stability, in order to make sure the mould is below working temperature, have taller hardness and strength. 4. Be able to bear or endure cold hot fatigue property has some of mould to be in the condition that heat repeatedly and cools in working process, make model antrum surface suffers pull, pressure changes the action of stress, cause the appearance chap and flake, increase attrition power, block up plasticity is out of shape, reduced dimension precision, bring about mould invalidation thereby. Cold hot exhaustion is one of main forms that heat up mould invalidation, help this kind of mould should be had taller be able to bear or endure cold hot fatigue property. 6. Be able to bear or endure when if plastic pattern is working,corrode sex has some of pattern, as a result of plastic in put in the element such as chloric, fluorine, be heated hind decomposes the strong aggressivity gas such as separate out HCI, HF, erode mould antrum surface, increase its surface surface roughness, aggravate grinds loss effect. (2) the production of mould of requirement of contented technical properties wants a course to forging commonly, a few working procedure such as cutting treatment, heat treatment. To assure the production quality of the mould, reduce manufacturing cost, its material should have rigid of processability of good forgeability, cutting, temper by dipping in water, temper by dipping in water to appear a gender to reach but grinding sex; Still should have small oxidation, decarbonization sensitivity and quench be out of shape craze tendency. 1. Forgeability has inferior hot forge to be out of shape fight force, plasticity is good, forging temperature range is wide, forge cracks cold cracking and separate out meshy carbide tendency is low. 2. Ball of anneal craft sex changes annealing temperature range wide, anneal hardness is low and fluctuant scope is little, the ball is changed rate is high. 3. Dosage of cutting processability cutting is big, cutting tool loss is small, treatment surface surface roughness is low. 4. It is good that when high temperature of sensitivity of oxidation, decarbonization heats, oxidation is fought to conceive, decarbonization rate is slow, to heating medium is not sensitive, inclination of generation hemp dot is little. 5. Even and tall surface hardness is had after rigid of temper by dipping in water quenchs. 6. After the gender quenchs, temper by dipping in water can obtain hard layer of deeper temper by dipping in water fully, use assuasive to quench medium can temper by dipping in water is hard. 7. Quench be out of shape craze tendency convention quenchs bulk changes small, appearance warp, distortion is slight, unusual be out of shape the tendency is low. Convention quenchs craze sensitivity is low, not sensitive to quenching temperature reachs workpiece figure. 8. But grinding sex emery wheel is opposite loss is small, without dosage of burn limit grinding big, not sensitive to emery wheel quality and cooling condition, produce gall and grinding crackle not easily. (3) contented economy asks to be in mould select material is, must consider economy this one principle, reduce production cost as far as possible. Accordingly, below the premise of contented performance characteristics, choose the price above all inferior, can use carbolic steel need not alloy steel, can use homebred material to need not import material. Additional, produce and supply a case what return market of Lv of take an examination when select material, place choosing steel is planted should as far as possible little and concentration, easy buy. CNC MillingCNC Machining