Sunday, October 25, 2015

Costs Of Different Metals Used In Mechanical Engineering By yaang.com

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
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
Ref 2010 ..I have enclosed a chart from the metalprices webpage to illustrate to range of titanium ingot pricing over a 12 month period
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
MaterialDensityCost/tonneRelativeCost /m3Relative
kg/m3/tonne/tonne/m3/m3
Carbon Steel7820550143011,0
Alloy Steels78208301,516490,61,5
Cast Iron72258301,515996,751,4
Stainless Steel778044508,134 6218,0
Aluminium alloys270022204,059941,4
Copper Alloys8900555010,149 39511,5
Zinc alloys710022204,015 7623,7
Magnesium alloys180040007,372001,8
Titanium alloys450017 00030,976 50017,4
Nickel alloys890018 00032,7160 20036,8

Current Metal Prices.. November 2010
I have tried to obtain some current (Nov 2010) metal prices from various internet sources and I list them below..These sometimes differ considerably from the table above
MaterialCost/tonneRelative Cost
(weight)
Relative Cost
(volume)
/tonne
Steel (Billet) LME-Nov-201032111
Steel (Hot Rolled Plate)-MEPS-July-20105051,61,6
304 Steel (Hot Rolled Plate)-MEPS-July-20102 5367,97,9
316 Steel (Hot Rolled Plate)-MEPS-July-20103 5351111
Tin- LME-Nov-201015 4584845
Aluminium Alloy - LME-Nov-20101 4074,.41,5
Aluminium - LME-Nov-20101 4254,41,5
Copper - LME -Nov-20105 27916,418,7
Zinc - LME -Nov-20101 4124,44,0
Nickel - LME -Nov-201014 3984451
Lead - LME-Nov-20101 4144,46,4
Titanium (ingot 6AL-4V) steelonthenet (11$/lb)15 7004928
Prices in dollars for 25mm round bar x 300mm long (0,00015m3 ) ...November 2010 (Onlinemetals (USA)

MetalPrice $1000/tonne1000/m3Relative cost
(weight)               
Relative cost
(volume)                 
Steel HR (A56)63,224,711
Steel CD (12L40)7,43,930,51.231.23
Alloy Steel (4130)9,995,341,21.661.66
St.Stl (304L)15,348,163,22.62.56
St.Stl (316L)20,6110,984,93.43.44
Aluminium (2011-T3)8,5813,135,44.21.43
Copper (C110)37,9117,5156,25.66.32
Brass (C360)25,311,7104,33.74.22
Bronze42,0919,5173,56.27.0
Titanium (6AL-4VG5)107984413117.8

Comparison of raw bulk material costs above with actual metal stock prices
Looking at the cost per tonne of HR steel in the form of a 1" dia round bar 1 foot long at 3200 against the LME price for the raw material in bulk for at 321/tonne illustrates the massive diiference in the price of raw materials to the actual price of materials as supplied for initial machining processes in small quantities.
Source: Zhejiang Yaang Pipe Industry Co., Limited (www.yaang.com)