The sintering waste in cemented carbide production.

1, peeling, alloy surface by edge crack, crack or become warped shell, serious when the scales of small thin skin, critical crack, even pulverization peeling;

Reason: due to the effect of contact of the briquetting of cobalt, decompose carbon gases in which the free carbon, resulting in briquetting strength decreased, resulting in a peeling.

Take the following measures to prevent peeling:

(1) the increase of hydrogen flow rate, lower water content in the hydrogen;

(2) reduce the subjective quantity, strictly control the forming agent addition amount;

(3) open the oven door sintering, the furnace air flow is laminar state;

(4) the guiding strictly control the furnace temperature, slow speed, decompose completely forming agent in the area;

(5) the boat close to block, or sprinkle a thick layer of packing, or reduce the amount of products on either side of the boat forward end;

2, drum up bubble: alloy products internal holes, and on the surface of its corresponding parts of a convex surface, this phenomenon is called drum up bubble;

Reason: there is a concentration of gas, sintered body usually has two kinds:

(1), gathered in the sintering process, the body in the process of sintering shrinkage, air from inside to the surface. If the sintered body has a certain size of impurities, such as alloy scrap, scrap iron, cobalt scrap, air to focus here already, until the liquid phase sintered body appeared, and densification, unable to discharge air, at least resistance of sintered body surface drum up bubble;

(2) the sintered body has generated a large amount of gas chemical reaction, when some oxide sintered body, in the event of a liquid phase after the reduction, the generated gas, this makes the products drum up bubble; WC - CO alloy is generally caused by a mixture of oxide agglomerate.

The porosity of the 3 holes: 40 microns called holes. Can lead to drum up bubble factors, all can form holes, just don't like drum up a large number of gas bubble, in addition, in the presence of sintered body to melt the metal wetting of impurities, such as "not good" pressure of big hole, or solid phase liquid phase sintered body exists serious segregation, can form the hole.

4, organization is not uniform: mixing.

5, deformation: sintered body appears irregular appearance change is called deformation.

(1) the uneven distribution of briquette density: because alloy density is the same;

(2) local severe lack of carbon sintered body: because of the lack of carbon liquid relatively reduced;

(3) the boat is not reasonable; Plate uneven;

6, crack:

(1) suppression of crack: because the briquetting dry stress relaxed didn't immediately, according to elastic recovery faster when sintering.

(2) oxide crack: because briquetting dry some serious oxidation, the oxidation thermal expansion volume and the oxidation of the different parts;

7, "dirty" : alloy fracture on the loose area called "dirty".

The reason: low carbon and high carbon is not appropriate. Factors that influence the carbon content of the sintered body, will influence the formation of a "dirty";

8, burnt: when the sintering temperature on the high side or holding time is too long can produce product burnt. Burnt products, make the grain coarsening, porosity increases, alloy performance significantly decreased. Owe to burn products metallic luster is not obvious, just burn can return.

Tungsten Carbide Strips Carbide Bar Tungsten Carbide Plate Tungsten Carbide Block to withstand the damage forces ability is crucial.
Six Star Hardmetal is a leading carbide tiles for drill stabilizer inserts manufacturer who supply more than 10 tons per month for TianJin Lilin Downhole Motors.