https://www.ancient.eu/article/1142/...inese-warfare/
this a good article about the cavalry discussion.
Although i don't know much about cataphracts at the time of the Han-Dynasty from chronicles and literature, i know at least a dozend despictions in art, where i have at least partially horsearmour. Further at least the western Han-Dynasty was well known for their strong cavalry forces and in percentage they were much higher than in previous our later dynasties. Especially under emperor Wu and while they established the four provinces at Korea the Han were notorious for there heavy and superior cavalry.