At the basic level, refrigerators are made up of the door, exterior cabinet, interior cabinet, or liners typically made of plastic, insulation, the cooling system, and the refrigerant. The majority of these components are made from plastic, with the fridge door coated in metal.
What are the materials used for the refrigerator, and what are the reasons behind these choices?
First, let’s explain the reasons behind these material choices.
- Plastic is relatively easy to shape and give life to. It’s easy to mold to produce the many designs that manufacturers want. Moreover, it’s also a cheap and practical material to use.
Small plastic banks or preformed plastic pieces are mainly used for the inner fixtures, such as the smaller fixtures like butter and egg trays and the salad crisper section.
- The refrigerator’s outer box/cabinet is made of a thin layer of aluminum steel and metal. This is typically the same material used for the refrigerator door, which explains the seamless and matching outer exterior.
In between the outer box and the inner cabinet is a layer of insulation typically made of fiberglass or polyfoam. This layer is multipurpose as it acts as a thermal insulator while at the same time, it also houses the other components of the fridge, such as the heater for hot water.
- The door and the external cabinet is made of sheet metalcore with an outer layer usually made of aluminum steel, plastic, or sometimes painted sheet metal. Very rarely is a plastic used as an outer skin.
Why is metal used for the refrigerator door?
- It adds durability to the fridge. This is especially important as the outer layer is exposed to the elements and the roughness that it is subjected to during the window of time that the manufacturers produce it. It arrives at the homes of customers.
- It protects the inner components generally made of more fragile materials such as foam, plastic, and other heavy metals for the compressor.
Why is metal used despite it being a terrible heat insulator?
- While metal is not an excellent material in retaining temperature, this is compensated because a layer of insulation foam is used between the outer metal shell and the inner cabinets.
The insulation makes the refrigeration system more energy-efficient. Remember that the way a refrigerator works is to keep the inside cold by keeping the hot air out. The additional layer of insulation aids this.
- The seams of the metal are also caulked to ensure even more effective insulation. The better the refrigerator’s insulation, the less energy it uses to keep cold.
- Moreover, it has excellent advantages that significantly overshadow the fact that it is not good at maintaining temperature. As mentioned, it is mainly used for its durability.
What are the other materials that could have been used aside from metal?
- Plastic is also a material of choice for the outer skin of the fridge. However, metal is more commonly used because it is generally more durable than plastic and can withstand more dire conditions that the fridge may be subjected to.
- Glass could have been a potential candidate, but it is too fragile to serve the purposes of a fridge’s exterior.
- On the other hand, wood is too porous and would invite bacteria to breed on the surface. This is something that you do not want for a kitchen appliance that is meant to keep food for longer.
This is unless a special coating was developed that will turn wood into a non-porous surface. Not to mention that wood is hefty, especially for a system already made with heavy components.
In conclusion, metal is the best material of choice because it serves its purpose well of being durable and protecting the rest of the refrigerator while having the least drawbacks.