Aleksandr Bobrishev has recently released a huge pack of materials for projects in Substance Painter.

The set is mostly about grunge materials, containing 45 smart files for your models Substance Painter (.spsm files). Basically, this pack can help you deal with basic surfaces presenting realistic surfaces. 

Please note that these materials can be used within Substance Painter 2018.2.3 and above. 

You can learn more here. 

Get the pack for $15