On 2018-08-08 14:48:54
heat resistant steel castings tools for machining
Basic requirements for cutting tools in the processing of heat resistant steel castings
With the promotion of technology, there are more and more kinds of heat-resistant steel castings, and the processing of heat-resistant steel castings is bound to be diversified, and the processing difficulty will be more and more, and more requirements will be put forward for the processing equipment of heat-resistant steel castings. So what are the specific requirements of metal heat treatment equipment in terms of cutting tools?
The first is about the requirements of the geometric parameters of the tool, in the processing of heat resistant steel alloy, the geometric shape of the cutting part of the tool should generally be considered from the front Angle, the back Angle. At the same time, the surface roughness of the cutting part should also meet the relevant requirements. The vacuum furnace of heat treatment equipment can improve the surface finish of the cutting part, which can reduce the resistance when the chips are crimped and improve the durability of the tool.
Secondly, in the processing of heat-resistant steel castings, the corresponding requirements on the material of the tool are put forward. Due to the large cutting force required, its tool must be strong and rigid enough to avoid flutter and deformation during cutting. This requires the selection of appropriate large cross section area of the knife, but also the use of high strength materials to make the knife.
1) Anti-oxidation steel (or heat resistant non-peeling steel) : this kind of steel at high temperature (generally in 550 ~ 1200℃) has good anti-oxidation and anti-corrosion performance at high temperature, and has a certain high temperature strength. It is used for manufacturing all kinds of heating furnace parts and heat exchangers. It is also used for manufacturing the combustion market of the heat turbine, the hanging melon of the boiler, the bottom plate of the heating furnace, the roll table and the tube of the furnace. Oxidation resistance is the main index, the component itself is not under great pressure.
2) Thermal strength steel: at high temperature (usually at 450 ~ 900℃), it is not only able to withstand considerable additional stress, but also has excellent anti-oxidation and anti-high-temperature gas corrosion ability. It is usually required to withstand periodic variable stress. It is usually used as rotor and blade of steam turbine and gas turbine, superheater of boiler, bolt and spring working at high temperature, inlet and outlet valve of internal combustion engine, oil hydrogenation reactor, etc.
In order to improve the machining accuracy of heat-resistant steel castings, it is required that the material of the cutting part of the tool has high wear resistance and can maintain its cutting performance at high temperature.
In view of the above requirements, the tool made of cemented carbide material is more suitable for the cutting of heat-resistant steel castings, which can not only achieve the ideal processing quality and precision, but also keep the tool in good condition and prolong its service life.