SU565488A1 - Ceramic cutting material - Google Patents

Description

one

This invention relates to a cutting ceramic material for steel, cast iron, graphite, wood and other materials.

A sintered cemented carbide-based alloy for machining is known, including a WC eutectic with carbon, A1203, SiO2, MgO, which has low wear resistance and strength 1.

The purpose of the invention is to increase wear resistance and strength.

This is achieved by the addition of sodium oxide and at least one metal from the group: cobalt, nickel, iron, with the following ratio of components, weight. %:

ABOZ54-94

MgO0.05-1.5

SiOa0.05-1.5

at least one carbide refractory metal from the group

TiC, ZrC, HfC5-30

at least one carbide refractory metal from the group

WC, Мо2С0.05-10

NaaO0.05-1.5

at least one metal from the group

Co, Ni, Fe0.05-1.5

The introduction of sodium oxide makes it possible to obtain a glass phase from oxides of Mg, Si, and Na in a ceramic material, which during sintering (hot pressing) improves the wettability of aluminum oxide and carbides of refractory metals with metals of the iron group, which leads to the formation of a dense material with high wear resistance and strength.

The process for producing the proposed ceramic cutting material is as follows.

Alumina, titanium carbide (pyrconium carbide, hafnium or a mixture of them), magnesium chloride, sodium silicate powders are loaded into a mill lined with hard alloy and milled

carbide balls in alcohol for 2-6 days.

During grinding, tungsten carbide (molybdenum carbide or a mixture of them) and cobalt (nickel, iron or their mixtures) are additionally solutely rubbed down. The ground mixture is hot pressed into blanks of the required shape, which are then ground with a diamond tool. The obtained refillable plates of ceramic cutting material are used as a cutting tool in the cutters with mechanical fastening.

Example. The mill lined with hard alloy VK-6, load

0.6% magnesium oxide in the form of MgCla-GHaO,

20% titanium carbide, 0.6% silicon dioxide and sodium oxide as Na2SiO3-9H2O, the rest is calcined alumina (). The mixture is ground for 6 days in the environment of ethyl alcohol. In the grinding process, 8% tungsten carbide and 0.5% cobalt are rubbed into the mixture. The mixture obtained as a result of grinding is dried, sieved and pressed to a press by hot pressing in graphite molds at 1650-1700 ° C. The duration of the hot pressing cycle is 20 minutes. Specific pressing pressure of 0.4 t / cm.

In the process of heating the charge during hot pressing, magnesium chloride decomposes to magnesium oxide; sodium silicate on sodium oxide and silicon dioxide. At 1100-1400 ° C, these oxides interact with each other to form a glass phase, which at 1400-1700 ° C becomes liquid, interacts with aluminum oxide and complex carbide, improves their wettability with cobalt. Moreover, sodium oxide contributes to the formation of a glass phase at relatively low temperatures and significantly improves wettability, as a result of which, after hot pressing, the products have increased wear resistance and strength at high density.

The durability of the proposed reush, its material when turning steel with a hardness of HRC 50-52 at a speed of 100 m / min exceeds the resistance of the OT by 3-4 times and makes it possible to process hardened steels at cutting speeds exceeding the cutting speed for TZOK4 alloy 1.5 -2.5 times.

Claims (1)

Invention Formula Ceramic cutting material, including oxides of aluminum, magnesium, silicon, carbide of refractory metals, from lich and w and so that, in order to increase wear resistance and strength, it additionally contains sodium oxide and, at least , one metal from the group; cobalt, nickel, iron, in the following ratio of components, weight. %: ABOZ54-94 MgO0.05-1.5 SiOs0.05-1.5 at least one carbide refractory metal from the group TiC, ZrC, HfC5-30 at least one carbide refractory metal from the group WC, MogS0.05-10 NazO0.05-1.5 at least one metal from the group Co, Ni, Fe0.05-1.5 Information sources, taken into account during the examination 1. Patent of Sweden No. 199288, cl. In OB 8/11, published. 1965.