What is the reason for front grinding when turning

This due to either a worn wheel bearing or a worn front drive arm.

The most common cause of a grinding noise when turning is a worn front wheel bearing. What happens is that the weight of the car is shifted on to that wheel as you make the turn causing the worn bearing to make a grinding noise.

Breaks Or wheel. Bearing

Possible drive shaft issue, does it occur in both directions (turning, left and right) or just one. Usually, drive shaft ware results in a knocking sound on turning either right or left depending on which side the ware is on. Grinding noise would suggest dry rather than worn shafts. I can't think of anything other reason for this that would not manifest itself with obvious damage and / or misalignment of either of the front wheels.

What direction of turn? Does noise happen at any speed ? As of now check outer cv joints, also inners while under neath check all 4 rubber boots for any holes , tears , grease spun on to any areas ? Check brake pads, shoes,mine made noise during turns due to loose pad vibrating clicking noise. Tell me if u find problem(s). Good luck