CNC Knowledge: “Exercise” is the most complete introduction!

What is caliber?

The caliber consists in heating the steel to the critical temperature and the preservation of heat for a certain period of time, then in cooling it at a critical cooling rate, in order to obtain a unbalanced tissue dominated by the hammer (it Benhera is also obtained according to the need or maintenance of the Olympic increase in the single phase) a heat treatment process. Tremp is the most used method to work in the steel heat treatment process.

The heat treatment in steel is approximately four basic processes: receipt, positive fire, extinction and fire recovery. The purpose of extinction is to transform refrigerated austenite for hammer or bell, to obtain fabrics of martensite or bell, then combined with fire at different temperatures to considerably increase the rigidity, hardness and resistance resistance The wear of steel sexuality, strength of fatigue and tenacity, in order to meet the different requirements of various parts and mechanical tools. You can also satisfy special physical and chemical properties such as ferromagnetic resistance and corrosion of certain special steel by extinction. Heat the metal part at an appropriate temperature and maintain it for a period of time, then dive into the rapid metal cooling metal treatment process in the extinction medium. Commonly used soil environments include the saline solution, water, mineral oil, air, etc. The caliber can improve the resistance to the hardness and abrasion of metal parts, it is therefore widely used in certain parts of various industries, mussels, measurements and requirements for resistance to wear on the surface (such as gears, Rolls, carburetable parts, etc.). Thanks to the combination of extinction and recovery of different temperatures, intensity, tenacity decreases and resistance to fatigue of metal can be considerably improved, and cooperation (complete mechanical performance) can be obtained to respond to different use requirements.

In addition, the caliber can also allow special performance steel to obtain certain physical chemical performance, such as caliber to improve magnetic iron steel and stainless steel to improve its corrosion resistance. The extinction process is mainly used for steel parts. When the commonly used steel is higher than the critical temperature, all or most of the tissue at room temperature will be transformed into auslite. Then soak the steel in water or oil to cool quickly, and the ainer is transformed into a companion. Compared to the other steel tissues, martensitis has the highest hardness. Quick cooling during the caliber will cause internal stress inside the room. To this end, the appropriate cooling method must be selected. Depending on the cooling method, the extinction process is divided into four categories: extinction of the monocial solution, dual agency extinction, extinction of notation of martensite and bell.

Quenching method

The one waterproof extinction part is cooled in a medium, such as water caliber and oil caliber. The advantage is that the operation is simple, easy to carry out mechanization and widely used. The drawback is that the stress of extinction in water is large and that the room is easy to deform and crack; The agency agency agency part of the agency first cooled at around 300 ° C in a strong cooling capacity, then cooled in an environment with a low cooling capacity, such as: the first extinction of the Water and oil caliber can effectively reduce the internal constraint of the transformation of martensitis, reduce the trend of the deformation and cracking of parts, can be used for the extinction of the room with complex shapes and a unequal cross section. The downside of the double liquid caliber is that it is difficult to grasp the conversion of the double fluid, the premature conversion is easy to harden and not hardened, and it is too late to crack. In order to overcome this gap, the rating extinction method has been developed. The classified caliber part is off in a low -temperature salt bath or an alkaline bathtub. The cooling method is called classification extinction. The cooling of cherishing is to make the temperature inside and outside the room more uniform. The hierarchical temperature was previously adjusted to a little higher than the MS point, and the temperature inside and outside the part is entering the Majélite district. Improved to the temperature class slightly lower than the MS point. The practice shows that the effect of notes below the MS point is better. For example, the high carbon steel molds are classified in an alkaline bath of 160 ° C, which can harden, deform and small, it is therefore widely used.

Temperature extinction
The room is off in the hot salt bath. While waiting for the temperature caliber for steel over carbon, the goal is to obtain the lower body to improve resistance, hardness, tenacity and abrasion resistance. Low carbon steel generally does not use temperature caliber. The caliber of the surface of the surface extinction is a local caliber method to extinguish the surface layer of the steel parts at a certain depth, and the cardiac part still maintains an unbearable state. During the surface caliber, the temperature of the rigid surface quickly reaches the temperature of the caliber. Induction extinction induction heating is to use electromagnetic induction to generate vortex in the room to heat the room. The cold is used as a solution of ice cream with a strong cooling capacity as extinction and cooling of the coolant. The local caliber is only the caliber which requires hardening parts. The quenching caliber by Qi refers to the caliber and cooling of the negative pressure, normally or high pressure in the high speed cycle in the vacuum and extinction and cooling of neutral and high pressure gases in the cycle to High speed. The surface caliber would only exhaust the surface layer of the part, in particular inductive caliber, the heating caliber of contact resistance, the caliber of the flames, the laser caliber and the electronic quench of the beam. Wind cooling calibration uses forced air or compressed air flow as extinction and cooling of the coolant. Salt caliber uses a solution of salt water as extinction and cooling of the coolant. Organic solution extinguishes the water solution from an organic polymer polymer as extinction and cooling of the coolant. The spraying caliber is cooled with a spraying solution as an extinction of the coolant. The spraying cooling part is caliber and cooling in the mist of water and air. The cooling room of the hot bath is off and cooled in hot baths such as the melting of salt, the fusion of the alkali, the fusion of the metal or the oil at high temperature, such as the caliber of the salt bath, Leading of the lead bath and alkaline bath caliber. After heating the two liquid extinction workers, first immersed in the environment with a strong cooling capacity, and immediately transferred to the middle with a low cooling capacity when the fabric is about to occur. Once the pressure extinction workers are heated, the caliber and cooling under specific tightening are maintained and its objective is to reduce the distortion of extinction and cooling. The exaggerated room from the surface to the hard -driving caliber of the heart. Once the temperature caliber part is heated, it is quickly cooled to the bellite temperature to transform the temperature interval. Once the graduated dip room is heated, the immersion temperature is slightly higher or slightly lower than that of the alkaline bath or the M1 alkaline bath to maintain the appropriate time. The caliber of the martensite. Asian analysis of Yamong’s caliber steel parts in the temperature interval AC1-AC3, extinction and cooling, and obtained the caliber of matelins and iron tissues. Direct extinction part to penetrate carbon and directly turn off the cooling process. After the two exinsisting workers were fueled and cooled, the AC3 temperature was first higher than AC3, and it turned off and dipped to refine the heart tissue. Once the cold caliber part quickly heated the Austrian auscultation, the heat of the heating area was transmitted to itself, so the Olympic body-body area can quickly cool the caliber.