English

English

  • facebook
  • twitter
  • linkedin
  • youtube
×
enter your keyword
latest news
  • 2020-04-01 China Government interviewed with Shunhao
    China Government interviewed with Shunhao

    Shunhao factory has been serving the machines and molds to melamine tableware factories, urea tableware factories, UF toilet seat and cover factories ...

  • 2020/04/08 Rice husk tableware
    Rice husk tableware

    Rice husk tableware Introduction: Rice husk tableware is to regenerate this discarded rice husk into natural, healthy and free of any harmful chemical...

  • 2020/04/05 Rationally view the harm of melamine tableware
    Rationally view the harm of melamine tableware

    Rationally view the harm of melamine tableware 1) What is melamine tableware Melamine tableware is made from melamine powder (known in the industry as...

  • 2020/04/05 Precautions and cleaning of melamine tableware
    Precautions and cleaning of melamine tableware

    Precautions and cleaning of melamine tableware 1. Main ingredients of melamine tableware raw materials: 100% melamine (domestically called A5 material...

718 Mould Steel-Introduction 3
Mar 23, 2020

718 mold steel-chemical composition

Element C carbon: Si silicon Mn manganese: Mo molybdenum Cr chromium Ni nickel standard
Content (%) 0.28 ~ 0.40 0.20 ~ 0.80 0.60 ~ 1.00 0.30 ~ 0.55 1.40 ~ 2.00 0.80 ~ 1.20 YB / T127-1997
China Melamine Mold
718 Mould Steel-Hardened
In order to improve the service life of the mold to more than 800,000 mold times, the pre-hardened steel can be implemented by hardening and low-temperature tempering. When quenching, first preheat at 500-600 ℃ for 2-4 hours, and then keep it at 850-880 ℃ for a certain period of time (at least 2 hours), put it in oil to cool to 50-100 ℃, and air-cool it. The hardness can reach 50 after quenching. -52HRC, in order to prevent cracking, a low-temperature tempering treatment at 200 ° C should be immediately performed. After tempering, the hardness can be maintained above 48HRC.

(Annealing: heating the steel to a critical point (Ac1 or Ac3) or above the recrystallization temperature, holding for a certain time, and then slowly cooling, so that the structure reaches a state of equilibrium.

Heat treatment
1). Quenching: Heat steel to 30 ~ 50 ° C above Ac3 or Ac1, and heat fast at a rate greater than the critical cooling rate after cooling 5. Cool. A martensitic structure is obtained and the steel is strengthened.
2). Normalizing: Heat the steel to 30 ~ 50 ° C above Ac3 or Acm, and then cool it in the air after holding to obtain the pearlite structure. The heat treatment process is called normalizing. Improve mechanical properties, refine grains and improve structure. Normalizing speed is faster than annealing.
3) Tempering: reheat the quenched steel to a temperature below Ac1, and mechanically cool after holding. It can be divided into low temperature tempering, middle temperature tempering and high temperature tempering.
4). Quenching and tempering: Generally, the heat treatment process of quenching and high temperature tempering is called quenching and tempering. It can obtain the sorbite structure, and can obtain the good comprehensive properties of strength and toughness. )
718 Mould Steel-Nitriding
Nitriding treatment can obtain high hardness surface layer structure, the hardness of the surface layer after nitriding reaches 650-700HV
(Surface hardness: 57-60HRC) The service life of the mold can reach more than 1 million times. The nitrided layer has the characteristics of dense structure and smoothness. The mold release property and the resistance to wet air and alkaline solution are improved.
China Melamine Tableware Mold
(Nitriding treatment: refers to a chemical heat treatment process that allows nitrogen atoms to penetrate into the surface layer of the workpiece at a certain temperature at a certain temperature. The products treated with nitridation have excellent wear resistance, fatigue resistance, corrosion resistance and high temperature resistance. Characteristics.
Common liquid nitriding, gas nitriding, ion nitriding.
Nitriding is also called diffusion nitriding. Gas nitriding was developed and industrialized for the first time by the German Fry around 1923. Due to the excellent abrasion resistance, fatigue resistance, corrosion resistance and high temperature resistance of the products treated by this method, its application range is gradually expanding. )
718 mold steel-critical temperature

Critical point Ac1
Start of transformation
PA temperature Ac3
All transitions
FA end temperature Ar1
AP temperature Ar3 when starting to cool down
Precipitation start A F temperature Ms during cooling
Markov transition start temperature Mf
Martensite transformation end temperature
Temperature (approximate) / ° C 770 825 640 755 335 180
(The definition of critical is English-of, relating to, or being a turning point or specially important juncture. Chinese-refers to the most basic conditions that should be possessed before changing from one state to another. For example, the critical temperature is the The maximum temperature of liquefaction. It is also used to describe the state of change after the development. The critical point is called the value when it reaches the critical point. The origin of the critical point comes from physics, which has phases due to different energy. (Such as ice → water → water vapor), the phase change represents a different boundary, so when a thing reaches the moment before the phase change, we call it critical, and the value at the critical time is called the critical point.)
718 die steel-linear (expansion) expansion coefficient

Temperature / ℃ 18 ~ 100 18 ~ 200 18 ~ 300 18 ~ 400 18 ~ 500 18 ~ 600 18 ~ 700
Coefficient of linear expansion (C) 11.9 × 10 12.20 × 10 12.50 × 10 12.81 × 10 13.11 × 10 13.41 × 10 13.71 × 10
718 mold steel-thermal conductivity

Temperature / ℃ 20 100 200 300 400
Thermal conductivity λ / W · (m · K) -1 36.0 33.4 31.4 30.1 29.3
Hot products
Our service
  • Workshop Show Workshop Show
    Presice machines, Experienced working team, clean factory quality, to make Melamine Tableware Mould.
  • Products Show Products Show
    Making variety of Melamine Compression Mould, Melamine Tableware Molding Machines, UF toilet seat cover pressing machine.
  • Video Show Video Show
    Video for Melamine Tableware Pressing machine, Melamine Tableware Mould.
  • OUR CERTIFICATES OUR CERTIFICATES
    Quality guranteed for Melamine mould and Melamine tableware molding machines and equipements from Shunhao Factory.
newsletter

chat now

Shunhao Moulds