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  • Tungsten: industry standards
  • ASTM E696-07(2013) Standard Specification for Tungsten-Rhenium Alloy Thermocouple Wire
  • ASTM B777-07(2013) Standard Specification for Tungsten Base, High-Density Meta
  • ASTM B760-07(2013) Standard Specification for Tungsten Plate, Sheet, and Foil
  • ASTM B631-93(2010) Standard Specification for Silver-Tungsten Electrical Contact Materials
  • AMS7879F Tungsten Carbide-Cobalt Powder, Cast and Crushed ISO Grade Classifications-Tungsten Carbide
  • Chinese government's regulations on tungsten resources
  • World tungsten supply is dominated by Chinese production and exports. China is also the world's largest tungsten consumer. To conserve its resources and meet increasing domestic demand, the Chinese government issues the total amount of tungsten ore that can be exploited, and adjusts export quotas every year. At the same time, government also increases or decreases export duties on many tungsten materials every year. In 2014, the first batch of tungsten export quotas is 13,582 tonnes, accounting for 70% of the total annual quotas.
  • Contents
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1
H
2
He
3
Li
4
Be
5
B
6
C
7
N
8
O
9
F
10
Ne
11
Na
12
Mg
13
Al
14
Si
15
P
16
S
17
Cl
18
Ar
19
K
20
Ca
21
Sc
22
Ti
23
V
24
Cr
25
Mn
26
Fe
27
Co
28
Ni
29
Cu
30
Zn
31
Ga
32
Ge
33
As
34
Se
35
Br
36
Kr
37
Rb
38
Sr
39
Y
40
Zr
41
Nb
42
Mo
43
Tc
44
Ru
45
Rh
46
Pd
47
Ag
48
Cd
49
In
50
Sn
51
Sb
52
Te
53
I
54
Xe
55
Cs
56
Ba
57
La
58
Ce
59
Pr
60
Nd
61
Pm
62
Sm
63
Eu
64
Gd
65
Tb
66
Dy
67
Ho
68
Er
69
Tm
70
Yb
71
Lu
72
Hf
73
Ta
74
W
75
Re
76
Os
77
Ir
78
Pt
79
Au
80
Hg
81
Tl
82
Pb
83
Bi
84
Po
85
At
86
Rn
87
Fr
88
Ra
89
Ac
90
Th
91
Pa
92
U
93
Np
94
Pu
95
Am
96
Cm
97
Bk
98
Cf
99
Es
100
Fm
101
Md
102
No
103
Lr
104
Rf
105
Db
106
Sg
107
Bh
108
Hs
109
Mt
110
Ds
111
Rg
112
Cn
113
Uut
114
Fl
115
Uup
116
Lv
117
Uus
118
Uuo