Factors influencing high-temperature compressive strength of alkaline phenolic resin-bonded sand

• The primary strength loss occurs between 600-800 °C due to intense resin decomposition. • Above 900 °C, structural reorganization of the carbon skeleton partially recovers strength. • Resin content, base sand type, and particle size significantly influence high-temperature compressive strength. • Findings provide critical data for optimizing sand casting processes to reduce defects like hot tearing and veining.