High speed steel cutter quenching process

A, process live - inspection material to pack card to drying, preheating, heating and cooling and oil ( Hot school) Or classification ( Cleaning) Or isothermal ( Cleaning) - - tempering in the check - cleaning to sand blasting, rust - alignment - final inspection. Second, the process operation ( 1) Live to see pattern, inventory quantity, check material, see the weld position, determine the quenching cooling way, light with light. ( 2) Choose the principle of fixture: a. Make the cutter uniform heat in the heating process. b。 Thin rod, flexible tool to hang. c。 Keeping balance of cutting tool in the operating process. d。 According to the heating part of the tool to choose reasonable fixture. f。 Isn't the clamping tool, the use of the wire bundle tight, pay attention to the wire not be broken at high temperature. ( 3) In the medium temperature salt bath furnace preheating: a. Preheat temperature: 800 - 850℃。 b。 Preheat time: 2 - for high temperature and heating time Three times. c。 Car cutter for billet, allowing the preheating in the electric box furnace, time is 40 - 60min。 d。 General tool preheating length more than about 20 mm weld. e. Furnace fixture with 2 - It is advisable to 4 CARDS. ( 4) In high temperature salt furnace heating: a. Heating temperature: 1270 1300℃（ W18Cr4V) 1220 - 1250℃（ W6Mo5Cr4V2） 1250 - 1270℃（ W9Mo3Cr4V） ( 5) Cooling way is as follows: a. Oil cooling: applicable to weld shape simple tools, such as turning tool, cutter, cutting head and cutting tools need to heat the school. Methods: cutting tools by a high temperature salt furnace, after appropriate oil cooling quenching oil without water, cold to 450 ℃ or so out of oil. b。 Grading: suitable for cutting tools in general. Methods: cutting tools by high temperature after the salt out of the furnace, stay in the classification of salt furnace, residence time is equal to the heating time, and then air cooling, hierarchical temperature is 550 - 600℃。 c。 Isothermal: suitable for thin rods easy bending tool, milling cutter and complex shape easy to deformation or cracking of the cutting tool. Methods: from the hierarchical salt bath after into the isothermal stay 2 - in the furnace For 3 h, isothermal temperature ( 280±10） ℃. e. Note: (1) cutting tools must be cool to room temperature before cleaning. (2) for easy to deformation of the hierarchical tool should be discharged in time after cleaning. (3) after the quenching of cutting tools to should take put down gently, in order to avoid bad, touch. ( 6) Tempering: in nitrate furnace. 一个。 Tempering temperature ( 560±10） ℃, the official before tempering furnace temperature for calibration. b。 Time after time: the meter to the temperature. Install card tool: 30 min, the barrel cutter: 60 90min。 c。 Tempering, general tool with tempering barrels or hierarchical framework tempering, short cutting tools ( Tap, forming tool, end mill, etc. ) , using the barrel tempering, barrels to core. Core specification: Ф 100 mm * 500 mm. Tempering bucket specification: Ф 400 mm x 500 mm. Easy deformation of rod cutter appropriate USES hanging tempering; Easy deformation flake knife and appropriate USES tempering fixture. e. Tempering times: three tool, isothermal knives, four times before tempering again cutting tools must be cool to room temperature. f。 Note: (1) classification or oil cooling cutting tools on the same day to temper. (2) by the operator notice metallographic examination after tempering tempering. (3) inadequate for identified as tempering, need to temper again. Third, high speed steel adopt a new technology of tempering ( Machine saw blade) W9Mo3Cr4V: 1280℃×40年代,560×1 h; W18Cr4V: 1310℃×20年代,560×1 h; Improve quenching temperature, shorten the time of heat preservation, refining high speed steel grain, dislocation martensite appear in the organization, to change the original single twin martensite structure, reduced the twin martensite relative content, high speed steel can be improved through strong toughness. g。 DNA operation procedures (1) DNA temperature: high temperature furnace: around 1280 ℃; The temperature in the furnace: 880 - 900 ℃ (2) the deoxidizer, outsourcing products deoxidizer. (3) the amount of each: 1 kg. (4) first sample after deoxidization, high temperature furnace oxide content analysis: w ( BaO) ≤0. 5%w( FeO) ≤0. 5%. (5) DNA operation close fan, slowly stir in deoxidizer and deoxidation 10 min after production can proceed. ( 3) High temperature salt furnace temperature measuring a. By using standard equipment calibration instrument member before quenching furnace temperature. b。 Metallographic calibration furnace temperature, metallographic test block: Ф 10 mm * 15 mm, heating time: 2 min. ( 4) The use of silicon controlled a. Before the start of check each part of the instrument is normal. b。 Startup should be manually, thyristor controlled current shall not exceed 10. A, voltage regulator for a current is not more than 150 a. c。 Voltage regulator work maximum current is 220 a long time. d。 Adjust temperature heating should be manual control when current is no more than 15 a. e. Close automatically during normal working. f。 Work for convenient operation, high temperature should be used first, and then gradually cool down. ( 5) The adjustment of the salt bath composition a. Regular analysis of salt bath composition, generally two times a month, according to the analysis results of salt bath composition adjustment and supplement. b。 To analyze the oxide content in salt bath regularly, deoxidization number increase or decrease according to the results of the tests. Temperature in the furnace: once a month. High temperature furnace: 2 times a month. c。 Water content of nitrate and alkali bath had a great influence on parts of cooling capacity. Classification of nitrate tank and alkali water content w ( H2O) Is 6%.