Unlock instant, AI-driven research and patent intelligence for your innovation.

Process for milling cermet or cemented carbide powder mixtures

A cemented carbide and cermet technology, which is used in the field of grinding cermet or cemented carbide powder mixtures, can solve the problems of long grinding time, clogging of the outlet, and the lower limit of the size of the grinding element.

Active Publication Date: 2012-04-18
SANDVIK INTELLECTUAL PROPERTY AB
View PDF12 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Although this gives cemented carbide powders of small particle size, the grinding time is still very long, and there are some technical drawbacks of this type of grinding machine, namely: wide particle size distribution, and due to the dead zone in the grinding chamber large particles
However, these types of mills have the problem of uneven distribution of the crushing elements in the crushing chamber
Some of these defects can be improved by using a circulation pump, but this ultrafine micro-grinder also has the following defects, that is, if the size of the body is reduced, the outlet can be blocked by the crushing element, so the size setting of the crushing element There is a lower limit

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Process for milling cermet or cemented carbide powder mixtures
  • Process for milling cermet or cemented carbide powder mixtures
  • Process for milling cermet or cemented carbide powder mixtures

Examples

Experimental program
Comparison scheme
Effect test

example 1

[0032] Invention 1, Ultrafine powders with additions of Co, vanadium carbide and chromium carbide in the amounts shown in Table 1 were produced using a horizontal agitation ball mill "Labstar" from the company Netzsch Feinmahl Technik equipped with a "Z" crushing system. 5 kg (dry) of the ingredients were weighed and mixed with 1.75 liters of ethanol as milling liquid. The slurry thus obtained was milled using 4400 grams of 1.15 mm diameter milling balls at a stirring speed of 1500 revolutions per minute for 50 minutes (10 minutes / kg), after which the furnish was spray dried.

[0033] For comparison, a powder with the same initial composition as Invention 1 was milled in a production ball mill (560 kg of powder in a 600 liter mill) for 40 hours (4.3 min / kg). The WC used has a particle size of 0.65 μm (FSSS) and the cobalt used is ultrafine cobalt from Umicore.

[0034] Table 1

[0035] Powder components before grinding in % by weight

[0036] The powder prepared ...

example 2

[0041] Invention 2, the same Labstar mill from Netzsch Feinmahl Technik as in Example 1 was used to produce fine grade particles with the addition of Co, vanadium carbide and chromium carbide in the amounts shown in Table 3. 10 kg (dry) of the ingredients were weighed and mixed with 2.7 liters of ethanol as milling liquid. The slurry thus obtained was milled using 4400 grams of 1.15 mm diameter milling balls at a stirring speed of 1650 revolutions per minute for 63 minutes (6.3 minutes / kg), after which the furnish was spray dried.

[0042] For comparison, the reference powder as reference 2 was milled for 40 hours (4.3 min / kg) in a production ball mill (560 kg of powder in a 600 liter mill). The carbides used have a particle size of 0.85 μm (FSSS) and the drills used are ultrafine drills from Umicore.

[0043] table 3

[0044] Powder components before grinding in % by weight

[0045] The powder prepared according to Invention 2 of the present invention and the po...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
sizeaaaaaaaaaa
Login to View More

Abstract

The present invention relates to a process for milling a cermet or cemented carbide powder. The process comprises circulating a slurry comprising powder(s) forming hard constituents, powder(s) forming binder phase and a grinding liquid through a grinding chamber. The grinding chamber comprises grinding elements and an agitator where the agitator is rotating around an essentially horizontal axis. The process according to the present invention provides a cermet or cemented carbide powder mixture at a significantly reduced milling time.

Description

technical field [0001] The present invention relates to a method of milling a cermet or cemented carbide powder mixture which significantly reduces the milling time. The invention involves circulating a slurry comprising a powder forming a hard component, a powder forming a binding phase, and a grinding liquid through a grinding chamber containing grinding elements and Rotating agitator. Background technique [0002] The main principles of cermet or cemented carbide production have been known for over 50 years. Powders that form hard components, such as TiC, WC, TiCN, etc., and powders that form a binder phase, are ground together with a grinding liquid and possibly with a pressing agent [w1] in a conventional ball mill. The slurry is then typically spray dried to form an agglomerated powder which is pressed into a green body and then sintered into a matrix for cutting tools and the like. [0003] The mills used to crush powders have historically been traditional ball mil...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): B02C17/00B02C17/18C22C1/00C22C1/05
CPCB02C17/205C22C1/051B02C17/1845B22F2998/00B02C17/1805B02C17/185B22F9/04B22F2009/045B22F2009/042B02C17/18C22C1/05B01F27/60
Inventor 马赛厄斯·蒂尔曼卡尔-约翰·玛德鲁德
Owner SANDVIK INTELLECTUAL PROPERTY AB