Manufactured loot materials are those materials ships drop when they explode, or scattered around a drop site when you pick up canisters.
To easily complete this Achievement simply equip yourself for bounty hunting, doesn't have to be a super high power ship, it all depends on the targets you will go after. I personally took a Viper MkIV which is not too expensive, loaded it with good laser hardpoints and went hunting.
As you hunt, select the targets that are easier for you to beat, and upon beating them scoop up all their loot. doing so 20-30 times will most likely unlock this Achievement for you.