Contents:
Typical Properties of Epoxy
Instructions for Use
How Much to Use

CERAC Silver-Filled Epoxy Cement

Introduction
CERAC silver-filled epoxy cement is a silver-colored thick paste containing the optimum ratio of silver powder to epoxy resin for maximum thermal and electrical conductivity and mechanical strength. The catalyst is a clear to yellow liquid. Both the epoxy cement and the catalyst should be stored in a refrigerator. This will give a shelf life of 6 months. Shelf life can be further extended to one year or more by freezing.

Typical Properties of Epoxy

Volume Resistivity	Less than 0.001 ohm-cm
Thermal Conductivity	.02(cal)(cm)/(sec)(cm2)(°C)
Pot Life (after catalyst addition)	30 min. 25°C (77°F)
Shelf Life (sealed container)	6 Months 25°C (77°F)
Use Temperature*	-50°C (-58°F) to 150°C (302°F)

* Epoxy retains physical properties to 150°C (302°F), but some outgassing may occur above 115°C (239°F)

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Instructions for Use
1. Degrease the backing plate, and roughen the bonding surface by lightly sandblasting or sanding with #400 sandpaper. The bonding surface of the target should also be slightly abraded with #400 sandpaper or similar materials.

2. Mask the edges of both the target and the backing plate with cellophane or some other easily removable tape. Also mask the surfaces of the target and backing plate not being bonded to prevent contamination from the epoxy cement.

3. Epoxy cement and catalyst should be at room temperature (approx. 21°C or 70°F) for best results.

4. Add the required quantity of catalyst to the epoxy cement and thoroughly mix. Use a 2.7 weight % ratio (2.7 parts catalyst per 100 parts epoxy). See "How Much To Use" section. No thinner should be used.

5. Spread the epoxy cement evenly and smoothly across the surface of the backing plate. Then, mound the epoxy cement towards the middle of the backing plate.

6. Position the target very carefully on the epoxied backing plate, and gently move the target back and forth slightly, while applying light pressure downward, until epoxy cement extrudes from ALL edges, and no gaps are noticed.

7. Remove excess epoxy cement with a small spatula, and be sure the target is parallel to the backing plate. Use a level table for curing. BOND WILL FORM OVERNIGHT AT ROOM TEMPERATURE OR FOR BEST RESULTS, HEAT TO 65°C (150°F) FOR ONE HOUR.

8. Remove all masking tape only when the bond is carefully cured.

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How Much to Use
For round targets, use the chart below. For other-shaped targets, calculate the surface area, and use amounts of epoxy and catalyst closest to a corresponding round target area.

Diameter Inches	Surface Area Square Inches	Wt. of Epoxy gms	Wt. of Catalyst gms
2	3.14	20	0.54
2.5	4.91	30	0.81
3	7.07	40	1.08
3.5	9.62	47.5	1.28
4	12.6	55	1.49
4.5	15.9	67.5	1.82
5	19.6	80	2.16
5.5	23.7	90	2.43
6	28.3	100	2.70
6.5	33.2	110	2.97
7	38.5	120	3.24
7.5	44.2	130	3.51
8	50.2	140	3.78
8.5	56.7	160	4.32
9	63.6	180	4.86
9.5	70.8	200	5.40
10	78.5	220	5.94
10.5	86.5	240	6.48
11	95	260	7.02
11.5	104	280	7.56
12	113	300	8.10

Phone:  414-289-9800 /  FAX: 414-289-9805  /   ceracinfo@beminc.com