Hardmetal compositions each including hard particles having a first material and a binder matrix having a second, different material comprising rhenium or a Ni-based superalloy. Tungsten may also be used a binder matrix material. A two-step sintering process may be used to fabricate such hardmetals at relatively low sintering temperatures in the solid-state phase to produce substantially fully-densified hardmetals. A hardmetal coating or structure may be formed on a surface by using a thermal spray method.