T12钢锉刀快速球化工艺怎么处理？-钢锉|锉刀-无锡市苏锋工具有限公司

国内钢锉基本上都是用T12钢制造。锉刀锻坯必须经过球化退火才
能满足随后机械加工的要求。虽然高碳钢的退火被认为是成熟的
传统工艺，但因其能耗高，周期长（一般需24h/炉），氧化脱碳
严重，生产效率低，促使人们对这一工艺的研究和改进。
Domestic steel files are basically made of T12 steel. The
forged billet must be spheroidizing to meet the
requirements of subsequent machining. Although annealing
of high carbon steel is considered to be a mature
traditional process, its high energy consumption, long
cycle (usually 24h / furnace), serious oxidation and
decarbonization, low production efficiency, prompt people
to study and improve this process.
1)球化退火工艺改进的理论依据。
1) the theoretical basis for improving spheroidizing
annealing process.
①根据有关文献的报导，在常规球化退火的组织中，粒（球）状
碳化物颗粒数（单位体积内或单位面积上）与加热奥氏体化时的
剩余碳化物颗粒数相同，由此认为球化退火后的粒（球）状碳化
物是由剩余碳化物长大而成。这就告诉我们加热奥氏体化时获得
的剩余碳化物颗粒数越多，球化后的粒（球）状碳化物也就越
多，球化越容易。
(1) According to the relevant literature, the number of
granular (spherical) carbide particles in the
conventional spheroidized annealed microstructure is the
same as that of the residual carbide particles in the
austenitized microstructure. It is considered that the
granular (spherical) carbide after spheroidized annealing
is formed by the growth of residual carbide. This tells
us that the more residual carbide particles obtained
during austenitizing, the more spheroidized carbide
particles, and the easier spheroidization.
②有研究证明，球化退火时有了粒状碳化物的核心只是球化的一
个方面，因为这些剩余碳化物在随后的奥氏体过冷分解中，既可
以作为共析分解的领先相，促使分解的另一相（α）作为受领相
在其表面上形核，从而形成了共析相的核心，此核心长大的结果
必然是两相相间交错分布层片状珠光体(PL)。此外，还有一种可
能，就是剩余碳化物粒化的现存的核心，但分解的另一相（α）
却不作为受领相，即不优先在碳化物表面上形核，而是在过冷奥
氏体内部深处单独形核，这种奥氏体分解产物的两个相分别独立
形核（不构成共析体核心）时，所造成的母相奥氏体内碳浓度分
布与共析转变时不同，它将促使碳化物和α相各自单独呈球状长
大，从而得到粒（球）状珠光体( Ps)。奥氏体化时得到的碳浓度
不均匀的奥氏体可明显加速Ps的形成过程。
(2) It has been proved that the nucleus of granular
carbides during spheroidizing annealing is only one
aspect of spheroidization, because these residual
carbides can be used as the leading phase of eutectoid
decomposition in subsequent subcooled decomposition of
austenite, and the other phase (a) of decomposition can
be nucleated on its surface as the receiving phase, thus
forming the eutectoid phase. The core of this core growth
is necessarily the interphase and intergranular
distribution of lamellar pearlite (PL). In addition, it
is also possible that the existing core of residual
carbide granulation, but the decomposition of another
phase (a) does not act as the receiving phase, that is,
does not take precedence in nucleating on the surface of
the carbide, but in the depths of the undercooled
austenite alone nucleation, the two phases of the
decomposition product of the austenite nucleate
independently (does not constitute eutectoid). The
distribution of carbon concentration in the parent
austenite is different from that in eutectoid
transformation. It will promote the growth of carbides
and alpha phases in spherical shape respectively, so that
the granular (spherical) pearlite (Ps) can be obtained.
The austenitizing of austenite can accelerate the
formation of Ps obviously.
③加热过程的控制理论。有研究者根据钢加热奥氏体化的转变图
和加热转变时奥氏体的形成及其内碳浓度变化的原理指出，通过
调整加热工艺的三个参数（加热速度、加热温度和保温时间）可
以控制奥氏体状态，从而满足前述理论的要求。在理论上控制仪
相消失的温度，时间以透烧为准。
3. Control theory of heating process. According to the
austenitizing transformation diagram of steel and the
formation of austenite and the change of carbon
concentration in the austenite during heating
transformation, it is pointed out that the austenite
state can be controlled by adjusting the three parameters
of heating process (heating speed, heating temperature
and holding time), so as to meet the requirements of the
above theory. In theory, the temperature of the
disappearance of the instrument is controlled by time.
2)快速球化退火工艺及效果。根据理论研究和现场测试结果，在
不改变退火前后的冷热加工工艺的情况下，在现有的几台不同的
炉内对不同类型和规格的锉刀毛坯进行快速球化退火试验，结果
见表3-6。球化退火的加热温度应根据所测炉子的热特性确定，而
保温时间除取决于炉子的热特性外，还与退火锉刀类型及装炉量
有关。保温时间总的来说由原来的5~6. 5h缩短到70~ 90min，降
温时间（指780℃奥氏体温度降至球化下限温度680℃所需的时
间）由原来的9.5~10h减少到4.5～5h，而且无跑温现象出现。
2) rapid spheroidizing annealing process and effect.
According to the results of theoretical research and
field test, the rapid spheroidizing annealing tests of
different types and specifications of file blanks were
carried out in several existing furnaces without changing
the cold and hot working processes before and after
annealing. The results are shown in Table 3-6. The
heating temperature of spheroidizing annealing should be
determined according to the thermal characteristics of
the furnace, and the holding time depends not only on the
thermal characteristics of the furnace, but also on the
type of annealing file and the amount of furnace. In
general, the holding time is shortened from 5-6.5 h to
70-90 min, and the cooling time is reduced from 9.5-10 h
to 4.5-5 h, and there is no running temperature
phenomenon.