Amir Daneshi

Study on the Effects of Abrasive and Coolant-Lubricant Types on Minimum Quantity Lubrication-MQL Grinding

In dry grinding, as there is no coolant lubricant to transfer the heat from the contact zone, generation of surface damages are not preventable. Promising alternatives to conventional flood coolant applications are also Minimum Quantity Lubricant (MQL) or Near Dry Machining (NDM) or Semi Dry Machining (SDM). This research has been conducted to study the influence of the abrasive and coolant-lubricant types on the minimum quantity lubrication (MQL) grinding performance. One type of CBN and three types of conventional wheels (corundum) were tested. The tests were carried out in presence of fluid, air jet and eleven types of coolant-lubricants, as well as in dry condition. The results indicate that the finest surface quality and the lowest grinding forces could be obtained when grinding with CBN wheels. In the case of conventional wheels, the coarser wheel induces much proper grinding results.

T-Dress, A Novel Approach in Dressing and Structuring of Grinding Wheels

Since the grinding wheel topography directly influences the grinding forces and material removal mechanism, the dressing of grinding wheels has a decisive role in the desired product quality achievement. A new dressing concept is introduced in this paper in order to reach the optimum chip formation condition. The novel dresser, T-Dress, creates a new structure on the grinding wheel owing to which remarkable reduction in grinding forces occur. These lead to the lower heat generation in the wheel-workpiece contact zone and consequently lower thermal damages. The experiments prove about 40% lower grinding forces in grinding of bearing steel materials, 100Cr6, when dressing with T-Dress compared to the case of dressing with conventional profile rollers with almost no difference in the ground surface roughness values.

Cylindrical Grinding by Structured Wheels

Structuring of the grinding wheels is a promising method to reduce the forces involved in grinding, especially during dry grinding. In this paper, one of the methods of grinding wheel structuring is presented. The structuring process was modeled to find the corresponding dressing parameters for the desired structure dimensions. The cylindrical grinding operation with the structured wheels was simulated to produce a spiral free ground surface. Afterwards, the dry grinding experiments with the structured and non-structured wheels were carried out to evaluate the efficiency of the structured wheels. The results revealed that the grinding forces can be reduced by more than 50% when the grinding wheels are structured, while the surface roughness values increase by 80%.