The detailed deformation mechanism and its microstructural modifications of white cast iron grinding balls used in comminution have been investigated using transmission electron microscopy (TEM) and XRD. De-shaping is the primary mode of ball consumption, and fracture of balls is a relatively uncommon failure mode. Deshaping is the manifestation of abrasive wear caused during the operation ...
The morphology and distribution of carbide precipitates strongly influence the mechanical and other properties of such a multiphase objects . If the relationship between subsurface service life and microstructure can be explored and controlled, the grinding service life of high chromium cast balls will be greatly improved.
The invention discloses a method for manufacturing high-chrome cast iron grinding balls. The casting and melting process includes melting blank samples at the temperature ranging from 1450 DEG C to 1500 DEG C in a 100KW and 10Kg medium-frequency electric induction furnace, casting at high temperature and controlling discharge temperature at 1400 DEG C around.
Grinding of these rocks is performed in crushers (coarse grinding) and fine grinding mills [1, 2]. Grinding balls are prepared from white cast iron alloyed with chromium and molybdenum. After melting in a high-frequency induction furnace and pouring into sand molds the hardness of grinding balls 20 – 120 mm in diameter may reach 700 HB.
At present, most of the grinding media used in cement industry are high-chromium balls. With the continuous development of cement grinding technology, the specific surface area and fineness of cement are required to be even higher. As a cement company, the correct selection of grinding materials is particularly important.
The grinding media may be the ore itself (autogenous grinding), bars, balls, or cylpebs, or even the ore itself together with a small amount of balls (semi-autogenous grinding). A survey found out that approximately 53% of the grinding circuits around the world use ball mills, and 38% use autogenous or semi-autogenous grinding, and therefore ...
On the one hand, the addition of chromium in casting grinding ball decreases the carbon content of the eutectic point and decreases the austenite area in the phase diagram. On the other hand, the type of carbide structure changes from reticulate M3C type to isolated M7C3 type, and the hardness of carbide increases, from 850 ~ 1100HV of M7C3 to ...
phology of M7C3 eutectic carbides in high chromium white cast iron. The presented results are part of the research con-cerning the possibility of improving the properties of chro-mium white cast iron alloying with vanadium, particularly impact toughness, which is used for grinding balls ore, coal, gravel, and cement.
NICKEL-CHROMIUM WHITE IRONS The oldest group of high-alloy ironsofindustrialimportance,the nickel-chromium white irons (Ni-Hard irons), have been produced for more than 50 years and are cost-effective materials for crushing and grinding. In these martensitic white irons, nickel is the primary alloying element, because3 to5%Niiseffectivein
Key Words: Grinding Ball; High Carbon Chromium GCR 15; hardness; wear resistance Introduction As a kind of grinding body, grinding ball requires high hardness, the higher the hardness, the better the wear resistance. From the carbon content of the grinding ball: With the increase of carbon content of the grinding ball, the higher the hardness of the grinding ball, the greater the wear ...
The microstructure of medium chromium white cast iron grinding ball can be regarded as a mixture of spongy reticulated M 3 C type cementite inlaid with austenite and alloy carbide transformation mainly M 7 C 3 type distributed in a three-dimensional open framework. The grinding balls' strength and toughness depend on the brittle M 3 C carbide phase's volume percentage and distribution.
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