When honing the inner hole, the workpiece is fixed and stationary. The honing head, which is equipped with grinding strips around and floating connected to the machine tool spindle, is used as a tool to remove a thin layer of metal from the machining surface through the relative motion of the honing head on the surface of the inner hole of the workpiece under a certain pressure. During honing, the grinding strip on the grinding head has three movements, namely rotary motion, axial reciprocating motion, and radial feed motion perpendicular to the machined surface. The first two operations are the main movements of the honing strip, and their synthesis causes the cutting trajectories of the abrasive particles on the machining surface to intersect without repetition.
Like ultra precision machining, the ratio of the large speed of the axial reciprocating motion of the grinding strip to the rotational motion speed forms the main parameter that affects surface roughness and productivity - the large cutting angle. Radial feed motion is the radial feed that achieves the cutting of the metal layer on the machining surface under pressure, and this radial feed rate changes with the pressure of the grinding strip on the inner hole surface.
When solving the inner hole shape, low surface roughness can be achieved due to the large number of abrasive particles simultaneously participating in cutting on the abrasive strip, the low pressure of the abrasive strip, and the less repetitive cutting trajectory of the abrasive particles. The abrasive properties, hardness, and binder of the grinding strip used in internal hole honing also directly affect the surface roughness and productivity of the machining process. White alumina and green silicon carbide are commonly used abrasives for honing strips. If 20-30% graphite powder is added to the abrasive, it can increase the friction and polishing effect of the abrasive particles on the machined surface, and reduce the roughness of the machined surface. Clay, resin, ｏｒ rubber are commonly used binders for honing strips, among which resin ｏｒ cementitious agents have good elasticity, can enhance the polishing effect of the honing strip and obtain lower surface roughness. They are generally used for semi precision honing and precision honing processing. The hardness of the grinding strip also has a significant impact on the honing process. Soft grinding strips have good self excitation, strong cutting effect, and high productivity, but the machined surface is prone to scratches. Hard grinding strips have poor cutting effect, but the surface roughness after machining is low.
