Introduction
This page is includes information on the costs of different metals used in mechanical
engineering. When producing mechanical components the material costs is
generally of limited significance . Other costs should be included when comparing
materials including design, procurement, production control, forming, machining, finishing,
distribution, etc etc. A component lifetime costs include maintenance, corrosion
protection and recovery (scrap).
The raw material cost for a particular component may be 20 times the cost if made from
one material compared to another on a weight to weight basis. However the lifetime
costs may be very similar if all of the other factors are also taken into consideration.
The material cost of a mass produced investment casting item may be 80% of the final cost. The
material cost of a single complicated machined item may be less than 10% of the final cost..
It is not possible to provide cost comparisons between different metals to any level of
accuracy. Each metal is varying in price on a day to day basis and different
alloys of the same metal can have significantly different costs.
A grade 7 titanium alloy costs twice as much as pure titanium (grade 1,2 or 3).
Comparing costs should only be based on final installed costs. eg. for a domestic,
industrial piping system a screwed steel system would cost about 40% more than a
copper piping system...
Example :
The price of a titanium /titanium alloy products results from a number of factors:
- Alloying grade .some grades e.g with Pd alloying component, can significantly increase
the price of the alloy.
- The purity of the grade... the more pure the higher the cost
- The test and inspection requirements;
- The procured quantities. The more ordered the lower the specific cost
- The geometry ..rolling or forging affects prices per volume or weight
- Demand ..e.g High defence demand for aerospace industry can result in higher metal prices
- Local economy.. Metal availability
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In year 2000 the price of titanium was about £13 000 to £43 000/tonne..
In 2002 the price of raw titanium was about to £8960/tonne.
In 2005 to-date the price of titanium has varied between £6000 and £9000 /tonne
Table showing relative metal costs
The table below can only really be used to give broad relative initial material costs. The figures
are based on a reference source originating about 2002
| Material |
Density |
Cost/tonne |
Relative |
Cost /m3 |
Relative |
| kg/m3 |
£/tonne |
£/tonne |
£/m3 |
- |
| Carbon Steel |
7820 |
550 |
1 |
4301 |
1,0 |
| Alloy Steels |
7820 |
830 |
1,51 |
6490,6 |
1,5 |
| Cast Iron |
7225 |
830 |
1,51 |
5996,75 |
1,4 |
| Stainless Steel |
7780 |
4450 |
8,1 |
34 621 |
8,0 |
| Aluminium/alloys |
2700 |
2220 |
4,0 |
5994 |
1,4 |
| Copper /Alloys |
8900 |
5550 |
10,1 |
49 395 |
11,5 |
| Zinc alloys |
7100 |
2220 |
4,0 |
15 762 |
3,7 |
| Magnesium /alloys |
1800 |
4000 |
7,3 |
7200 |
1,8 |
| Titanium /alloys |
4500 |
17 000 |
30,9 |
76 500 |
17,4 |
| Nickel alloys |
8900 |
18 000 |
32,7 |
160 200 |
36,8 |
Current Metal Prices.. November 2005
I have tried to obtain some current material prices from various internet sources and I list
them below..These sometimes differ considerably from the table above
| Material |
Cost/tonne |
| £/tonne |
| Steel (Hot Rolled Plate) |
400 |
| 304 Steel (Hot Rolled Plate) |
2768 |
| 316 Steel (Hot Rolled Plate) |
1628 |
| Tin- LME |
3588 |
| Aluminium Alloy - LME |
1044 |
| Aluminium - LME |
1257 |
| Copper - LME |
2576 |
| Zinc - LME |
991 |
| Nickel - LME |
7644 |
| Lead - LME |
635 |
| Titanium |
9000.. |
Comparison of costs above with actual metal stock prices
I have obtained from the internet (ref link 7 below) a typical cost for a 50mm dia mild
steel bar 0,3m Long. (actually 2in. dia x 1 foot).
The price for 2in dia x 1 foot long hot rolled mild steel round A36 as of Dec 2005 is
$13,89 which is approximately £8. The price falls as the quantity ordered
is increased. This stock has an approximate volume of 0,0006m3. Using the value of £4301 /m2 (from the illustration table above) results in a
price of about £2,53. I provide this information to reinforce the note
that the table above is useful only for indicating relative raw metal prices..
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