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Titanium Standard

Chemical Composition & Mechanical Properties according to ASTM Standards

ASTM Ç¥ÁØ¿¡ µû¸¥ È­ÇÐÀû Á¶¼º ¹× ±â°èÀû ¼ºÁú
DESIGNATION GRADE 1 GRADE 2 GRADE 3 GRADE 4 GRADE 5 GRADE 7 GRADE 11
COMPOSITION(%MAX) È­ÇмººÐ
Oxygen (O) 0.18 0.25 0.35 0.40 0.20 0.25 0.18
Nitrogen (N) 0.03 0.03 0.05 0.05 0.05 0.03 0.03
Hydrogen (H) 0.015 0.015 0.015 0.015 0.015 0.015 0.015
Carbon (C) 0.08 0.08 0.08 0.08 0.08 0.08 0.08
Iron (Fe) 0.20 0.30 0.30 0.50 0.40 0.30 0.20
Aluminium (Al) - - - - 5.5~6.75 - -
Vanadium (V) - - - - 3.5~4.5 - -
Palladium (pd) - - - - - 0.12~0.25 0.12~0.25
Residual each (total) 0.10(0.4) 0.10(0.4) 0.10(0.4) 0.10(0.4) 0.10(0.4) 0.10(0.4) 0.10(0.4)
ASTM Ç¥ÁØ¿¡ µû¸¥ È­ÇÐÀû Á¶¼º ¹× ±â°èÀû ¼ºÁú
DESIGNATION GRADE 1 GRADE 2 GRADE 3 GRADE 4 GRADE 5 GRADE 7 GRADE 11
MECHANICAL PROPERTIES ±â°èÀû ¼ºÁú
Tensile Strength MPa min. 240 345 450 550 895 345 240
ÀÎÀå°­µµ (ksi) (35) (50) (65) (80) (130) (50) (35)
Yield Strength MPa 170~310 275~450 380~550 483~655 830 275~450 170~310
Ç׺¹°­µµ (ksi) (25~45) (40~65) (55~80) (70~95) (120) (40~65) (25~45)
Elongation % min.
(¿¬½ÅÀ²)
24 20 18 15 10 20 24
Hardness HV typical
(°æµµ)
100~150 160~200 180~220 200~280 310~350 160~200 100~150

Physical Properties

Comparison of Physical Properties with those of other Metals

°¢ ±Ý¼ÓÀÇ ¹°¼º ºñ±³ Á¤º¸
Item Atomic no. Atomic wt. Density (g/cc) Melting point (¡ÆC) Linear thermal expansion coefficient (/¡ÆC) Specific heat (J/g-¡ÆC) Thermal conductivity cofficient (W/m¡¤K) Specific electrical (¥ì¥Ø-cm) Electrical conductivity to Cu(%) Young's modulus (GPa) Poisson's ratio
Titanium 22 47.90 4.5 1,668 8.4x10-6 0.53 17.0 55 3.1 116 0.34
Iron 26 55.85 7.9 1,530 12¡¿10-6 0.44 76.2 9.7 18 200 0.31
18-8 Stainless steel (SUS 304) - - 7.9 1,400~1,420 17¡¿10-6 0.50 16.2 72 2.4 195 0.3
Aluminum 13 26.97 2.7 660 23x10-6 0.90 210 2.7 64 68 0.33
Aluminum alloy (7075) - - 2.8 476~638 23¡¿10-6 0.96 120 5.8 30 71.7 0.33
Magnesium 12 24.32 1.7 650 25¡¿10-6 1.03 159 4.3 40 44 0.35
Magnesium alloy (AZ-31B) - - 1.8 605~630 26¡¿10-6 1.0 96 9.3 19 45 0.35
Nickel 28 58.69 8.9 1,453 15¡¿10-6 0.46 60.7 9.5 18 207 0.31
Nickel alloy (monel) - 8.8 8.8 1,300~1,350 14¡¿10-6 0.43 21.8 48 3.6 170 0.29
Hastelloy C - - 8.9 1,305 11.3¡¿10-6 0.43 11.1 130 1.3 205 -
Copper 29 63.57 8.9 1,083 17¡¿10-6 0.39 385 1.7 100 110 0.34
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  • 1. 18-8 stainless steel : Cr(18%)-Ni(8%)-Fe(R)
  • 2. Monel : Ni (70%)-Cu (30%) Hastelloy C : 54Ni-17Mo-15Cr-5Fe-4W
  • 3. AZ-31B : AI (3%)-Zn (1%)-Mn (0.2%) - Mg(R)
  • 4. 7075 : Tempered and quenched ultra-super duraluminum [Cu (1.6%)-Mg (2.5%)-Cr (0.3%)-Zn (5.6%)-Al (R)]
  • 5. Crystal structure
    ¥á Titanium (¡Â885¡ÆC) : close-packed hexagonal lattice a=2.9504 ¡Ê c/a=1.587
    ¥â Titanium (¡Â885¡ÆC) : body-centered cubic lattice a=3.3065 ¡Ê
  • 6. Latent heat of fusion : 14.5 cal/g Permeability : 1.0001

Corrosion Resistance

Comparison of corrosion resistance between titanium and other metallic materials

ƼŸ´½°ú ´Ù¸¥ ±Ý¼Ó Àç·á °£ÀÇ ³»½Ä¼º ºñ±³
Classification Corrosion medium Concentration (%) Temperature (¡ÆC) Titanium SUS304 SUS316 Hastelloy C
Inorganic acids Hydrochloric acid 1 25 A B A A
Boiling D D D C
10 25 B D D D
Boiling D D D D
Sulfuric acid 1 25 A A A A
Boiling D D C B
10 25 B B B A
Boiling D D D B
Nitric acid 10 25 A A A A
Boiling A A A B
65 25 A A A B
Boiling A B B D
Organic acids Acetic acid 10 Boiling A A A A
60 Boiling A B B A
Ossalic acid 10 25 A C B A
30 Boiling D D D A
Formic acid 10 25 B B B B
25 60 D C B B
Lactic acid 10 Boiling A B B B
85 Boiling A D D B
Alkali Sodium hydroxide 10 100 A A A A
40 Boiling D B B B
Potassium carbonate 5 Boiling A A A A
20 Boiling A A A A
Inorganic chlorides Sodium chloride 25 25 A* B* B* B
Boiling A B* B* B*
Ammlnium chloride 40 25 A* B* B* A
Boiling A* C* B* A*
Zinc chloride 20 Boiling A* D D D
50 Boiling A D D D
Magnesium chloride 42 25 A* A* A* A
Boiling A A* A* A*
Iron chloride 30 25 A* D D C
Boiling A D D D
Inorganic salts Sodium sulphate 20 25 A A A A
Boiling A A A A
Sodium sulfide 10 25 A A A A
Boiling A B B A
Sodium chlorite 5 25 A C C C
15 25 A C C C
Sodium carbonate 30 25 A A A A
Boiling A A A A
Organic compounds Methyl alcohol 95 25 A A A A
Carbon tetrachloride 100 Boiling A B B B
Phenol Saturate 25 A A A B
Formaldehyde 37 Boiling A A A B
Gas Chlorine Dry 25 D A A A
Humid 25 A* D D D
Hydrogen sulfide Dry 25 A C B A
Humid 25 A B A B
Ammonium 100 40 A A A A
100 A A A A
Others Seawater - 25 A A A A
100 A* B* B* A*
Naptha - 80 A A* A* A
180 A A* A* A
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  • A : ¡´0.125mm / year B : 0.125~0.5mm / year C : 0.5~1.25mm / year D : ¡µ1.25mm / year
  • *Local corrosion such as pitting and crevice corrosion resistance