Grinding cracks can be attributed to
glazed wheels, inadequate coolant,
excessive feed rate or attempting to
remove too much material in one pass.
Grinding cracks develop where there is localized overheating of the base material.
Surface cracks in hardened objects can be caused by improper grinding operations. Thermal cracks are created by stresses from localized overheating of the surface under the grinding wheel.
Overheating can be caused by using the wrong grinding wheel, a dull or glazed wheel, insufficient or poor coolant, feeding too rapidly or cutting too heavily. Grinding cracks are especially detrimental because they are perpendicular to the object surface and have sharp crack tips that propagate under repeated or cyclic loading.
Grinding cracks are typically at right angles to the grinding direction, are very shallow and are often forked and sharp at the root.
When located in high stress areas, such
cracks may result in fatigue failures caused
by residual stresses.
Materials that have been hardened or heat treated are susceptible to grinding cracks because uncracked they retain high residual stresses from quenching.
During grinding, localized heating added to entrapped stresses can cause surface ruptures. The resulting cracks are usually more severe and extensive than typical grinding cracks.
Grinding cracks develop where there is localized overheating of the base material.
Surface cracks in hardened objects can be caused by improper grinding operations. Thermal cracks are created by stresses from localized overheating of the surface under the grinding wheel.
Overheating can be caused by using the wrong grinding wheel, a dull or glazed wheel, insufficient or poor coolant, feeding too rapidly or cutting too heavily. Grinding cracks are especially detrimental because they are perpendicular to the object surface and have sharp crack tips that propagate under repeated or cyclic loading.
Grinding cracks are typically at right angles to the grinding direction, are very shallow and are often forked and sharp at the root.
When located in high stress areas, such
cracks may result in fatigue failures caused
by residual stresses. Materials that have been hardened or heat treated are susceptible to grinding cracks because uncracked they retain high residual stresses from quenching.
During grinding, localized heating added to entrapped stresses can cause surface ruptures. The resulting cracks are usually more severe and extensive than typical grinding cracks.