Vitrobond Ingot Capping Compound for concrete compressive strength testing is a solution that’s easy to store and handle. This sulfur-based dark gray compound is carbon-filled and melts and pours smoothly for consistent results.

Compressive strength exceeds 8,000psi (34.4kPa) at two hours and increases to 9,000psi (48.3kPa) at seven days. Ingots come in 50lb (23kg) cartons, each with ten 5lb ingots. Pieces break easily for melting to a pouring temperature of 280°–300°F (138°–140°C).

Physical strength ratings are 600psi tensile strength and 1,300psi modulus of rupture by ASTM C307 methods. The compound must not be heated above 320°F (160°C). Using excessive-release oil may affect cap strength. Price varies by order quantity.