MATERIAL SCIENCE GUIDE

Material Properties Comparison

Choosing the perfect material for your part means understanding its fundamental properties. This guide provides a detailed comparison of common plastics and metals, highlighting their strengths and weaknesses.

Plastics Comparison Table

Property	ABS	Polycarbonate (PC)	Nylon 12 (PA12)	POM (Delrin®)	PEEK
Density (g/cm³)	1.04	1.20	1.01	1.41	1.31
Tensile Strength (MPa)	45	65	50	60	95
Flexural Modulus (GPa)	2.3	2.4	1.7	2.8	3.7
Impact Strength (kJ/m²)	20 (Izod Notched)	60 (Izod Notched)	5 (Izod Notched)	5 (Izod Notched)	8 (Izod Notched)
HDT @ 0.45 MPa (°C)	88	138	145	110	152
Key Feature	Tough, easy to finish	Unbreakable, clear	Durable, functional	Low friction, stiff	Extreme temp/chem res.

Note: Values are typical and can vary by specific grade, fillers, and test conditions.

Metals Comparison Table

Property	Aluminum 6061-T6	Stainless Steel 316L	Titanium Grade 5 (Ti-6Al-4V)	Copper C110
Density (g/cm³)	2.70	8.00	4.43	8.94
Tensile Strength (MPa)	310	570	950	220
Yield Strength (MPa)	276	290	880	69
Thermal Conductivity (W/m·K)	167	16	7	391
Corrosion Resistance	Excellent	Excellent (chlorides)	Excellent (immune)	Good (tarnishes)
Key Feature	Lightweight, machinable	Corrosion res., strong	Strength-to-weight, biocompatible	High electrical/thermal cond.

Note: Values are typical and can vary by specific grade, heat treatment, and test conditions.

Material Properties FAQ

Which is more important, Tensile Strength or Yield Strength?

For most engineering applications, **Yield Strength** is more important. It defines the point at which a material will begin to permanently deform. Designing below the yield strength ensures your part will return to its original shape after a load is removed. Tensile strength (or ultimate tensile strength) is the absolute maximum load before the material breaks.

How does temperature affect these properties?

For most materials, strength and stiffness generally decrease as temperature increases, and vice versa. Some materials, like high-performance polymers (PEEK, Ultem) and superalloys (Inconel), are specifically designed to maintain their properties at very high temperatures, making them ideal for demanding environments.