Disintegrated is often used, but it isn’t that accurate, as it implies being broken into small constituents or parts. There were large parts that survived the initial explosion, and the breakup was partially due to being subjected to forces the vehicle was not designed for (I.e., the shuttle being twisted sideways at mach speeds). The crew compartment stayed intact on the way down, with evidence that some of them were still conscious during part of the ballistic free-fall.