In AX2012 R2 CU7 there was an update that allow a product data manager or someone involved in managing BOMs, routes etc to use a case to track the history and changes on that related information. In this video I give a quick walk through of setting up and using the case.
This gives a good starting point for adding some control to that data. There are other features that you might want to look at for other aspects of control like the electronic signature. As where there are ISV partners that have written add-ons for Dynamics AX that add further revision management control for BOMs.