Automation equipment consist of standard and non-standard components. The quality of non-standard component is related to the normal running of whole equipment and material is the key factor for quality, so for designer, it is really important to know the performance and application of different material well.
The main category of material is: metal and non-metal.The sheet below is the most common material category for automation industry.
Low-carbon steel:
carbon content ≤0.25%, low strength and hardness, high plasticity and tenacity, good forgeability and weldability. Normally used for low load components with no heat treatment, such as Q235 and steel section. SPCC/SECC/SGCC also belongs to low-carbon steel and mainly used for sheet metal case.
Low-carbon steel:
carbon content 0.3%—0.6%, high strength and hardness, good machineability, low weldability. Mainly used for high load components. Due to high carbon content, material has heat treated ability. 40#、45#、50# steel(most common medium carbon steel) mainly used for axis components.
Stainless steel:
good resistance to acid-base medium corrosion and not easy to get rust. The most usual grand in automation equipment is SUS303/SUS304. 303 has a good machineability and normally is bar material. 304 has a poor machineability and mainly used for sheet metal.
Aluminum alloy:
low density, high strength, the most usual material in automation equipment. Different grades has different properties. 5052 mainly used for sheet metal, 6061 for CNC machining and the widely used material. Normally 6063 is aluminum section, 7075 is aviation aluminum for high strength occasion. Anodizing is the most common surface treatment for Aluminum alloy.
Cooper alloy:
consist of red copper, brass, cupronickel. Red copper is fine copper, mainly used as electrode for EMD(Electric Discharge Machining). Brass is copper and zinc alloy. It has good mechanical property, mainly used for conductive, heat conduction and corrosion resistant structural components. Bronze is copper-tin alloy. It has castability, anti-frication property and good mechanical property, mostly used for high strength and corrosion resistant components such as casting gear and sleeve.
commonly known as acegal. It has a high strength and stiffness, and good anti-friction property. In automation equipment, POM is mainly used for low load and light weight occasion such as product positioning checking fixture and link stopper.
PU can stimulate various material properties, the most common one is rubber performance PU which can used for overmolding product, bumper block, shaft coupling and small rolling wheel. Hardness range from shore 25A to shore 90A.
high transparency, suitable for transparent, insulative and low strength components such as equipment security door protective cover.
commonly known as “king of plastic”. It has great chemical stability, corrosion resistance, airtightness and high self-lubrication. PTFE mainly used as frictional sliding material, sealing components and anti-adhesive components. Material price is rather expensive.

Low temperature or cold resistance, corrosion resistance (not include nitric acid ), low water absorption, excellent electrical insulation. Mainly used in corrosion resistant material containers.

good insulation property, high temperature resistance, light weight and high rigidity. Mainly used for testing equipment and checking fixture.
The picture below shows material selection of an automation equipment non-standard components: