- Paramagnetism
- Particle Reinforcement Composites
- Passivity
- Pauli Exclusion Principle
- Pearlite
- Periodic Table
- Peritectic Reaction
- Permeability (Magnetic)
- Permittivity
- Phase
- Phase Diagram
- Phase Transition
- Phonon
- Phosphorescence
- Photoconductivity
- Photomicrograph
- Photon
- Piezoelectric Materials
- Piezoelectricity
- Pilling-Bedworth Ratio
- Pitting corrosion
- Plain Carbon Steel
- Planck’s Constant
- Plane Strain
- Plane-Strain Fracture toughness
- Plastic
- Plastic Deformation
- Plasticizer
- Point Defects
- Poisson’s Ratio
- Polar Molecule
- Polarization (Wave)
- Polarization (Electric)
- Polarization (Corrosion)
- Polarization (Ionic)
- Polarization (Orientational)
- Polycrystal
- Polymer
- Polymer Matrix Composite
- Polymorphism
- Powder Metallurgy
- Precipitation Hardening
- Precipitation Heat Treatment
- Prepreg
- Pre-stressed Concrete
- Primary bond
- Principle of Combined Action
- Process of Annealing
- Proeutectoid cementite
- p-Type Semiconductor