Nowadays the merging of metal and hardcore is quite common, common enough to coin the phrase metalcore. A similar concept was practiced in the 80's, though the sound was quite different, and back then it was called crossover. Crumbsuckers was one of the more well-known such bands (and arguably one of the most metallic), with their 1986 album Life of Dreams regarded as a classic of said genre, mixing hardened guitars (almost thrash, though thrash hadn't yet fully caught on) with the looseness of punk/hardcore. They followed up with Beast On My Back two years later, but the more metallic leanings of that album weren't as well received by fans, and by the early nineties the band was finished. Several members embarked on a melodic metal venture called Heavy Rain, but that band was short-lived. The rhythm section of Gary Meskil and Dan Richardson went on to Pro-Pain, while Chuck Lenihan ended up with Genitorturers.

Source : http://www.bnrmetal.com/v2/bandpage.php?ID=Crum