Stainless steel grinding instructions

stainless steel 304 csp parts to achieve surface quality and precision requirements, usually grinding methods. Due to the large stainless steel toughness, thermal conductivity, low elastic modulus, so there are problems in the grinding often:

1) easy to adhere to clog the wheel; 2) the machined surface is easy to burn;

3) hardening serious; 4) of the workpiece deformation.

Difficult to see, select and grinding wheel grinding fluid directly affects the efficiency and precision. This paper jam affecting adhesion and surface roughness factors were studied.


2 Experimental conditions and methods

Specimen material selection 1Gr18Ni9Ti, its mechanical properties: σb = 530MPa, σ = 40%, hardness HB = 187 specimen size diameter φ50mm, length 300mm, φ50 cylindrical surface of fine cars, both ends of the plane hit the center hole. Experiments on MGB1420 cylindrical grinder, grinding wheel for P400 × 40 × 203, cylindrical grinding grinding way, in order to improve the reliability of the test results, repeat the test, observe the average effect, eliminate the influence of random factors, while try to keep the grinding conditions are basically the same, by changing the wheel size, hardness, abrasives, grinding fluid replacement, grinding to examine the impact on the amount of grinding effect.


3 experimental results

3.1 wheel size affect adhesion rate

Selection of corundum, hardness K, respectively, for the four wheel size 36,46,60,80 number of specimens were cylindrical grinding, grinding length of 600mm, detection adhesion rate, the finer the grinding wheel, stick attached to the more serious, this is due to the presence of voids between the grains, the grinding chips can be stored in the voids; and finer grinding wheel, voids smaller chip space quickly lose the wheel, causing blockage.


3.2 Effect of the adhesion rate of wheel hardness

Selection of the abrasive is fused aluminum oxide, particle size 46, hardness was H, J, K, L grade wheel, the specimen grinding, grinding stroke 600mm, detection adhesion rate. The higher the hardness of the wheel, the more severe adhesion. This is due to the low hardness of the grinding wheel, abrasive grains in the grinding force, easy to fall off from the wheel surface, the formation of new chip space, easy to plug.


The impact on the adhesion rate of 3.3 abrasive

Commonly used abrasive wheel has two kinds of corundum and silicon carbide green, experiments show that the impact of the two abrasive adhesion rate, the difference is not big, green silicon carbide can reduce the sticking slightly because of the crisp and sharp.


3.4 Effect of the surface roughness of grinding fluid

Respectively, using the three liquid emulsion, an inorganic salt grinding fluid and oil-based grinding fluid, was added sulfur, chlorine and other extreme pressure additives, observed after processing of the workpiece surface roughness, the flow rate of the grinding liquid is 20L / min, the grinding stroke of 600mm, the experimental results shown in Table 3.

As can be seen, the surface tension, containing extreme pressure additives, surface quality obtained by grinding. Rational use of grinding liquid, can improve heat dissipation, the grinding liquid can grinding debris and abrasive shedding flush, while in the metal surface to form a film, a lubricant, reducing surface roughness.


3.5 The amount of influence on adhesion rate of grinding

Workpiece speed, feed rate and grinding depth has little effect on the process, can be seen from Table 2, changing the depth of grinding, has little effect on the adhesion rate.


4. Conclusion

1) Stainless steel factory grinding, reducing wheel adhesion blocking is an important factor to improve grinding efficiency, processing should always trim wheel, keep a sharp cutting edge.

2) stainless steel grinding wheel selection of good self-sharpening wheel is the main objective, generally used in low hardness of the wheel is good, but you can not select the hardness is too low, otherwise the grains did not blunt it off. J recommended use level.

3) To reduce the grinding wheel adhesion obstruction, should be used in coarse-grained wheel. When coarse granularity with the No. 36, 46, when the choice of 60 grit grinding.

4) When the grinding of stainless steel, the use of GC grinding wheel improves the grinding efficiency.

5) grinding fluid selection must take into account the role of lubrication and cleaning of two, adequate supply, the choice of the surface tension, the emulsion containing extreme pressure additives, a high surface quality.

6) Select the amount of grinding allowance can be determined based on.

7) during the experiment found that the wheel organization and binders have some influence on the grinding process of stainless steel, is currently restricted by experimental means, pending further study.