The CAR (corrective action) would be a good method to manage the risks. I had a chance to send few of them to the vendors when they send defected materials to my company. The corrective action gives the other company information that something is incorrect. By fixing their problems the risk that their material will be defective again will decrease. Also it’s good to do vendor evaluation. The vendor evaluation log show which vendors are better in delivering the right material in proper time period. Of course pricing also have to be taken into consideration. The risk of choosing worst vendor is often taken if he can supply the company with materials for lower price.

Thanks