Appearance

Compact

Color

white

Ivory

Ivory

Content

99%

99.5%

99.7%

Density

g／m^３

3.8

3.9

3.9

Water Absorption

％

0

0

０

Vickers Hardness

Gpa

15.5

15.7

17.2

Flexural Strength

Mpa

310

370

380

Compressive Strength

Mpa

2160

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---

Young's Modulus

Gpa

360

370

380

Poisson's Ratio

－

0.23

0.23

0.23

Fracture Toughness

Mpa.m^1/2

3～4

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---

Coefficient Of Thermal   Expansion

40-400°C

x 10^-6/k

7.2

7.2

7.2

40-800°C

x 10⁶/k

8.0

8.0

8.0

Thermal Conductivity　 20°C

W(m.k)

29

32

32

Specific Heat Capacity

J(g.k)

0.79

0.78

0.79

Thermal Shock Resistance   (in water)

°C

200

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---

Dielectric strength

kv/mm

15

15

15

Volume resistivity

20°C

Ω.cm

>10⁴

>10⁴

>10⁴

300°C

Ω.cm

 10¹⁰

10¹³

10¹³

500°C

Ω.cm

10⁸

10¹⁰

10¹⁰

Dielectric constant 　1MHz

－

9.9

9.9

9.9

Dielectric loss angle 　1MHz

x 10^-4

2

1

1

Loss factor

x 10^-4

20

10

10

Nitric Acid（60%）90°C, 24 Hours

Weightlessness

mg/cm²

0.1

---

      0.05

Sulphuric Acid（９５%）9５°C, 24 Hours

Weightlessness

mg/cm²

0.33

---

0.22

Caustic Soda（３０%）８０°C, 24 Hours

Weightlessness

mg/cm²

0.26

---

0.04