Specifications

4J29 Kovar
1.Pass: ISO9001 2008 certification;
2.fine after-sale services;
3.small order accepted;
4.samples available;

4J29 KOVAR

4J29 is also known as kovar alloy,ASTM F15,Nilo-K, UNS K94610 ,(FeNi29Co17),

YB/T5231-2005 ,(FeNi29Co18),Lockinvar,Alloy 12B,Sealing Alloy. Iron Nickel cobalt.

 

Note:

A Nickel-Iron-Cobalt, controlled expansion alloy containing 29% Nickel. It's coefficient of expansion (which decreases with rising temperature to the inflection point), matches the expansion rate of borosilicate glasses and aluminia ceramics. Applications include glass to metal seals in applications requiring high reliability or resistance to thermal shock, ie. high-power transmitting valves,transistor leads and heaters and photography flash bulbs.

 

1.Alloy grades and chemical composition consistent with the provisions of table 1

the chemical composition of Kovar(%)
C	P	S	Mn	Si	Cu	Cr	Mo	Ni	Co	Fe
Not more than≤
0.03	0.020	0.020	0.5	0.30	0.20	0.20	0.20	28.5-29.5	16.8-17.8	balance

 2.table 2

 

Status code	State	Tensile strength,N/mm2
R 1/4I 1/2I 3/4I I	Soft state 1/4 Hard state 1/2 Hard state 3/4 Hard state Hard state	<585 585-725 655-795 725-860 >860

                                                                                  

3.Strip tensile strength in line with the provisions of Table 3

Status code	State	Tensile strength,N/mm2
R 1/4I 1/2I 3/4I I	Soft state 1/4 Hard state 1/2 Hard state 3/4 Hard state Hard state	<570 520-630 590-700 600-770 >700

 

4.Alloy average linear expansion coefficient in line with the Table 4                  

Alloy Grades	Specimen heat treatment system	The average linear expansion coefficient a,10-6/ oC
		20-300 oC	20-400 oC	20-450 oC
kovar	In hydrogen atmosphere heated to 900 ± 20 oC, insulation 1h, and then heated to 1100 ± 20 oC, insulation 15min, to not more than 5 oC / min rate of cooling to below 200 oC released.	-----	4.6-5.2	5.1-5.5

 

 

 

 

 

 

 

 

 

5.Alloy typical expansion coefficient                                                 

Alloy Grades	The average linear expansion coefficient a,10-6/ oC
	20- 200oC	20- 300 oC	20- 400oC	20- 450oC	20- 500oC	20- 600oC	20- 700oC	20- 800oC
kovar	5.9	5.3	5.1	5.3	6.2	7.8	9.2	10.2