- Calcination
- Capacitance
- Carbon-Carbon Composites
- Carburizing
- Case-hardening
- Cast iron
- Cathode
- Cathodic protection
- Cation
- Cement
- Cementite
- Ceramic
- Ceramic Matrix Composites
- Cermet
- Chain-folded model
- Charpy impact test
- Coarse Pearlite
- Coercivity
- Cold Working
- Colorant
- Compacted graphite iron
- Concentration polarization
- Conduction band
- Conductivity
- Congruence Transformations
- Continuous cooling transformation
- Copolymer
- Corrosion
- Corrosion Fatigue
- Corrosion Penetration Rate (CPR)
- Coulomb force
- Covalent Bond
- Creep
- Crevice Corrosion
- Critical resolved shear stress (CRSS)
- Cross-Linked Polymers
- Crystalline
- Crystallinity
- Crystallites
- Crystallization
- Crystal structure
- Crystal system
- Curie Temperature