Summary
- Acetal (POM) is rated better with
- Halogenated hydrocarbons (+53 points); Alkalis (+52 points); Salts and salt solutions (+24 points)
- Aluminium is rated better with
- Phenols (+86 points); Organic acids (+33 points); Amines and nitrogen compounds (+21 points); Mineral acids (+11 points)
- Within 10 points of each other
- Oxidising agents and halogens; Alcohols and glycols; Ketones and aldehydes; Esters and ethers; Aromatic hydrocarbons; Fuels, mineral oils and aliphatic hydrocarbons; Vegetable and animal oils, fats, essential oils; Foods and beverages
Points are the difference in the share of rows rated A or B.
The two materials
Acetal (POM)
Polyoxymethylene (acetal)
Acetal (POM) resists many organic solvents and fuels. Strong acids and oxidising agents degrade it.
Rated rows: 956. A 41 %, B 32 %, C 12 %, D 15 %
Aluminium
Aluminium
Aluminium relies on a thin oxide layer. Strong acids, strong alkalis and mercury compounds destroy that layer.
Rated rows: 968. A 60 %, B 9 %, C 16 %, D 16 %
Share of rows rated A or B, by chemical class
How often the two ratings agree
Chemical classes were assigned by this site, not by the source. Mixtures and trade products without a clear class are not counted.
By chemical class
| Chemical class | Acetal (POM): rated A or B | Aluminium: rated A or B |
|---|---|---|
| Mineral acids | 5 % (63 rows) | 16 % (63 rows) |
| Organic acids | 34 % (64 rows) | 67 % (64 rows) |
| Alkalis | 76 % (21 rows) | 24 % (21 rows) |
| Salts and salt solutions | 76 % (197 rows) | 52 % (194 rows) |
| Oxidising agents and halogens | 43 % (63 rows) | 45 % (62 rows) |
| Alcohols and glycols | 96 % (57 rows) | 98 % (59 rows) |
| Phenols | 0 % (14 rows) | 86 % (14 rows) |
| Ketones and aldehydes | 91 % (35 rows) | 97 % (35 rows) |
| Esters and ethers | 88 % (68 rows) | 94 % (71 rows) |
| Amines and nitrogen compounds | 74 % (38 rows) | 95 % (39 rows) |
| Aromatic hydrocarbons | 100 % (14 rows) | 100 % (14 rows) |
| Fuels, mineral oils and aliphatic hydrocarbons | 96 % (73 rows) | 100 % (78 rows) |
| Vegetable and animal oils, fats, essential oils | 100 % (45 rows) | 100 % (48 rows) |
| Halogenated hydrocarbons | 80 % (70 rows) | 27 % (71 rows) |
| Foods and beverages | 100 % (46 rows) | 96 % (46 rows) |
Where the ratings differ most
Rows where the two ratings at 20 °C are at least two grades apart: 192 in total, the first 40 shown.
| Chemical | Concentration | Acetal (POM) | Aluminium |
|---|---|---|---|
| Acetic Acid | 100 % | D | A |
| Acetic Acid | 90 % | D | A |
| Antimony Trichloride | anhydrous | D | A |
| Bromomethane | technical grade | A | D |
| Butylphenol | 100 % | D | A |
| Butyric Acid | D | A | |
| Calcium Hypochlorite | saturated | A | D |
| Calcium Hypochlorite | aqueous | A | D |
| Caraway | ground | A | D |
| Chloromethane (Methyl Chloride) | technical grade | A | D |
| Chromic Acid | 10 % | D | A |
| Chromic Acid | 20 % | D | A |
| Copper Sulfate (Copper Vitriol) | aqueous | A | D |
| Copper(II) Nitrate | saturated | A | D |
| Copper(II) Nitrate | aqueous | A | D |
| Cresol | D | A | |
| Formic Acid | 98-100 % | D | A |
| Gear Oil, EP (Hypoid), 110°C | D | A | |
| Hydrocyanic Acid (Hydrogen Cyanide) | technical grade | D | A |
| Hydrocyanic Acid (Hydrogen Cyanide) | aqueous | D | A |
| Lead(II) Acetate | A | D | |
| Lead(II) Acetate | aqueous | A | D |
| Nitric Acid | 100 % | D | A |
| Oleum (Fuming Sulfuric Acid) | 10 % SO3 | D | A |
| Oxalic Acid | D | A | |
| Oxalic Acid | aqueous | D | A |
| p-tert-Butylphenol | technical grade | D | A |
| Phenol | 10 % | D | A |
| Phenol | 100 % | D | A |
| Phosphorus Oxychloride | D | A | |
| Phosphorus Oxychloride | 100 % | D | A |
| Phosphorus Pentachloride | D | A | |
| Phosphorus Pentoxide | technical grade | D | A |
| Phosphorus Trichloride | D | A | |
| Potassium Carbonate | saturated | A | D |
| Potassium Carbonate | aqueous | A | D |
| Potassium Hydrogen Carbonate | saturated | A | D |
| Potassium Hydroxide | 1 % | A | D |
| Potassium Hydroxide | 10 % | A | D |
| Propionic Acid | D | A |
Rating scale
- A very good resistance
- B good resistance
- C limited resistance
- D not resistant
- – no data
- K no general statement possible
A rating marked * is an estimate in the source, not a test result. An estimate is given as one value without a temperature.
More comparisons
Frequently Asked Questions
Is Acetal (POM) or Aluminium more chemical-resistant?
Of 947 chemicals rated for both materials at 20 °C, Acetal (POM) and Aluminium share the same rating in 395 rows (42 %). Acetal (POM) is rated better in 205 rows and Aluminium in 347 rows.
How do Acetal (POM) and Aluminium compare for chemical resistance?
Based on 947 chemicals tested for both: Acetal (POM) is rated better with Halogenated hydrocarbons, Alkalis, Salts and salt solutions. Aluminium is rated better with Phenols, Organic acids, Amines and nitrogen compounds, Mineral acids. They perform similarly with Oxidising agents and halogens, Alcohols and glycols, Ketones and aldehydes, Esters and ethers.
About this data
The ratings come from the chemical resistance list published by Bürkle GmbH, which compiled them from raw-material manufacturers’ data. They describe laboratory tests on the raw material at 20 °C and 50 °C.
A finished part also sees pressure, mechanical stress, welds and mixtures that a laboratory test does not. Treat the rating as a first filter and test under your own conditions before relying on it.