When you buy a refrigerator, first of all you pay attention to volume, energy consumption and design. But few people think about what metal is the refrigerator made of? - and this determines its strength, durability and even cooling efficiency. Modern models combine several types of metals, each of which performs its own function: from stainless steel in the body to copper in the tubes of the cooling circuit.
In this article we will look at what metals are used in key components of the refrigerator - from the outer casing to the compressor. You will learn why manufacturers refuse aluminum in some parts, how to recognize quality metal when purchasing, and what to do if rust appears on the body. And also what innovative alloys they are beginning to displace traditional materials in premium models Samsung, Liebherr and Bosch.
1. Refrigerator body: steel vs plastic with metal coating
The outer body is the “face” of the refrigerator, and here manufacturers use tricks. Most budget models (for example, ATLANT or Indesit) have a body made of thin sheet steel with powder coating. This material is cheap, but is vulnerable to scratches and corrosion if the coating is damaged. More expensive refrigerators (say, Liebherr Premium) use stainless steel - it does not rust, but requires special care (we will talk about it below).
Interesting fact: some models (for example, Samsung Family Hub) combine metal with plastic coated metalized film. Visually, such a case looks like stainless steel, but in fact it is coated plastic. It’s easy to check: tap on the surface - metal will make a dull sound, plastic will make a ringing sound.
- 🔹 Galvanized steel —a budget option, susceptible to corrosion if the coating is damaged.
- 🔹 Stainless steel —premium segment, resistant to rust, but expensive.
- 🔹 Aluminium - light but soft (rare, usually in retro models).
- 🔹 Plastic with metal coating - imitation of stainless steel, cheap, but short-lived.
⚠️ Attention: If chips appear on the body of the refrigerator, immediately seal them with transparent tape or special paint for metal. Moisture on bare steel will lead to rust within 2-3 months.
2. Internal walls of the chamber: aluminum or plastic?
If the body can be steel or plastic, then the internal walls are almost always made of food-grade aluminum or plastic with antibacterial coating. Aluminum conducts heat better, which helps maintain even temperatures, but it is soft and easy to scratch with a knife or fork. Plastic is cheaper and stronger, but it conducts cold worse, which is why condensation can accumulate in the corners of the chamber.
In premium models (for example, Miele K 12020 S) they are used anodized aluminum —it is stronger than usual and resistant to corrosion. And in refrigerators with a system No Frost internal walls are often made of plastic, because it does not accumulate ice.
| Material | Pros | Cons | Where it is used |
|---|---|---|---|
| Aluminium | Good thermal conductivity, lightweight | Soft (scratched), can oxidize | Chamber walls, shelves |
| Plastic | Cheap, durable, does not rust | Poor thermal conductivity, can absorb odors | Budget models, No Frost systems |
| Anodized aluminum | Durable, corrosion resistant | Expensive | Premium segment (Miele, Liebherr) |
| Stainless steel | Hygienic, durable | Heavy, expensive | Professional refrigerators |
In refrigerators with the “Antibacterial coating” function, silver ions embedded in plastic or aluminum are often used. This is not a separate metal, but an additive that inhibits the growth of bacteria.
3. Heat exchanger and tubes: why copper displaces aluminum
The heart of the refrigerator is cooling circuitthrough which the refrigerant circulates. Previously, tubes were made of aluminum, but today most manufacturers have switched to copper. Why?
- 🔧 Copper better conducts heat, which increases cooling efficiency by 15–20%.
- 🔧 Copper is resistant to corrosion from freon (unlike aluminum, which oxidizes over time).
- 🔧 Less risk of leaks: copper tubes are stronger and less likely to crack during vibration.
However, copper is more expensive, so in budget models (for example, Birusa or Nord) sometimes aluminum heat exchangers are also found. Their disadvantage is that over time they can become clogged with oxidation products, which leads to loss of cooling capacity..
How to check the material of the tubes?
If the refrigerator has already been purchased, inspect the back wall: copper tubes have a reddish tint, aluminum tubes have a silvery tint. In new models, the tubes are often hidden under the panel, so check the material in the technical data sheet (section “Refrigerant and heat exchanger”).
⚠️ Attention: If your refrigerator with an aluminum heat exchanger begins to freeze worse, do not rush to change the compressor. It may be enough to clean the system of oxides (this is done in service centers using special equipment).
4. Compressor: steel, aluminum and rare alloys
The compressor is the most loaded component of the refrigerator, and here the metals are selected taking into account strength and heat resistance. The compressor housing is usually made from cast iron or high-strength steel, since it must withstand pressure up to 20 atmospheres. The following are used inside:
- 🔩 Aluminum pistons - lightweight, but wear out faster than steel.
- 🔩 Steel valves - durable, resistant to high temperatures.
- 🔩 Copper windings in the electric motor (for better conductivity).
In inverter compressors (for example, in LG Inverter Linear Compressor) are often used special alloys with the addition of nickel, which reduce friction and increase efficiency. Such compressors last longer than conventional ones, but also cost 2-3 times more.
5. Shelves and containers: what metal is safe for food
Shelves in the refrigerator can be:
- 🍳 Glass with a metal frame (aluminum or stainless steel).
- 🍳 Plastic (in budget models).
- 🍳 Perforated metal (in professional refrigerators).
Glass shelves with aluminum edging - the most common option. Aluminum is safe here because it does not come into direct contact with products. Premium models (for example, Samsung RS68A8840S9) use shelves made of tempered glass with stainless steel —they can withstand weight up to 30 kg.
But metal grids (as in refrigerators for restaurants) is made from AISI 304 stainless steel - it does not rust even with constant contact with moisture. At home, such shelves are rare, but they can be purchased separately (for example, for storing bottles).
Do not use abrasive detergents
Wipe dry after washing
Do not place hot pots (risk of deformation)
Check fastenings every 6 months-->
6. Door seals: hidden metal that no one thinks about
It would seem, what does metal have to do with it if the seal is a rubber gasket? In fact, it is hidden inside metal spring (usually made of steel or aluminum), which ensures a tight fit of the door. If the spring breaks or rusts, the seal loses its elasticity, and the refrigerator begins to “suck” warm air.
In cheap models, the spring can be made of ordinary steel without protection —over time it rusts, especially if the refrigerator is in a damp room. In high-quality seals (for example, in Bosch Serie 6) they use stainless wire or aluminum with an anti-corrosion coating.
⚠️ Attention: If the seal stopped holding its shape, don’t rush to change it. Try heat it with a hairdryer (temperature 50–60°C) and stretch by hand - sometimes this restores elasticity. If the spring inside is broken, the seal will have to be replaced.
7. Innovative materials: what is replacing traditional metals
Manufacturers are actively experimenting with new materials to make refrigerators lighter, more environmentally friendly and more efficient. This is what is already used in modern models:
- 🔬 Composite materials (plastic + metal chips) - light but durable. Example: body Haier Cascade.
- 🔬 Graphene coating - improves the thermal conductivity of the internal walls (used in concepts Samsung).
- 🔬 Magnesium alloys - lighter than aluminum, but stronger. So far used only in the premium segment.
- 🔬 Self-cleaning alloys with the addition of titanium - prevent the formation of mold.
One of the most promising areas is replacement of copper in heat exchangers with aluminum alloys with nano-coatingThis allows you to save. thermal conductivity, but reduce weight and cost. For example, in refrigerators Hisense already use aluminum tubes with internal nickel coatingwhich extends their service life.
FAQ: Frequently asked questions about metals in the refrigerator
Is it possible to paint the refrigerator body if it rusted?
Yes, but only with special metal paint (for example, Hammerite or Dulux Metal Shield) First remove the rust with sandpaper, degrease the surface with acetone and apply a primer in 2-3 layers, allowing it to dry. enamel - it will fly around quickly.
Why was the body made of stainless steel in Soviet refrigerators (ZIL, Minsk), but now it is almost never used?
In the USSR, stainless steel was cheaper due to government subsidies for metallurgy. Now it is expensive, so manufacturers save money by using galvanized steel or plastic. premium models (for example Liebherr or Gorenje).
Is it harmful if the inner walls of the refrigerator are made of aluminum?
No, if it is food grade aluminum (grades A5 or A6). It undergoes special processing and does not emit harmful substances. It poses a danger only oxidized aluminum (with a white coating) - it must be removed with citric acid.
Is it possible to replace aluminum tubes in the cooling circuit with copper ones?
Technically yes, but this is a complex and expensive process. You need to:
- Drain the freon and cut the old pipes.
- Solder new copper pipes (argon welding is required).
- Evacuate the system and charge the refrigerant.
The cost of work is from 10,000 rubles, so it is cheaper to buy a new refrigerator.
Why are the internal walls of No Frost refrigerators plastic and not metal?
Plastic does not accumulate condensation, which is critical for systems No FrostMetal (even aluminum) can. become covered with frost, and plastic with an anti-condensation coating prevents its formation. The downside is that plastic dissipates heat less well, so powerful ventilation is important in such refrigerators.