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Description for Henkel 681
• Non-Corrosive - High Performance Magnet Bonding Adhesive • Vapors are Non-Corrosive to Copper Surfaces • Nonflammable • No Activator Required • Excellent Gap Filling Ability • High Shear, Peel, & Impact Strength • Rapid Room Temperature Cure • Fixtures Parts in 30 to 60 seconds • Environmentally Friendly – 100% Solids • 100% Cure Outside of Bondline •<br/>Brand Bondmaster Chemical Resistance Salt Spray Application Type Bond 1 Part or 2 Part 2-Part Material Form Liquid Substrate Ferrite, Copper, Glass, Alnico, Steel, Neodymium iron boron, Epoxy-Coated Metal, Metals, Painted Metal, Samarian cobalt Industry Generators, Magnets, DC motors, Electric motors Manufacturer Henkel Chemistry Acrylic, Toughened Cure Method Part A/Part B Cure Temperature (°C) 20 to 25 Room Temperature, 20 to 25 Cure Time (min) Rapid, 480 Viscosity (cPs) 90,000, 13,500 Color Dark Green High Temperature Resistance (°C) 155 Low Temperature Resistance (°C) -65 -
Technical Data for Henkel 681
Overview
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Chemical Resistance
- Chemical Resistance - Salt Spray
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Application Type
- Adhesive - Bond
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1 Part or 2 Part
- 2-Part
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Material Form
- Liquid
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Industry
- Electronics - Generators
- Speakers
- Industrial - Basket, Housings, Pole piece
- Magnet - Magnets
- Motors - DC motors, Electric motors
- Construction - Frames
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Chemistry
- Toughened
- Acrylic
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Cure Method
- 2-Part Cure - Part A/Part B
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Color
- Green - Dark Green
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Brand
- Bondmaster
Specifications
Cure Specs
Cure Temperature (°C) 20 to 25 Room Temperature, 20 to 25 Cure Time (min) Rapid, 480 Viscosity (cPs) 90,000, 13,500 Test Method Fixture or Handling Strength Time (min) 0.50 to 1.00 Test Method Work / Pot Time (min) 0.50 Test Method Thixotropic Thixotropic Mix Ratio 1:1 (by volume), 1:1 (by weight) Bond Strength
Structural/Load-Bearing Structural Peel Strength (piw) High, 20 to 25 Test Method Shear Strength (psi) High, 3,000 to 3,500, 2,000, 250 Test Method Impact Strength (psi) High, 14 Test Method Material Resistance
High Temperature Resistance (°C) 155 Impact Resistance Impact resistance Low Temperature Resistance (°C) -65 Moisture/Humidity Resistance Moisture/humidity resistance Hardness
Shore D Hardness 70 to 75 Test Method Other Properties
Specific Gravity 0.980 Flash Point (°F) 260.6 % Solids (%) 100 Business Information
Shelf Life Details Part A, Uncured, Part B, Uncured Shelf Life Temperature (°F) 77, 77 Shelf Life (mon) 6, 6 -
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Best Practices for Henkel 681
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Surface Preparation
The 681 adhesive requires no surface preparation on most metal, ferrite, and glass surfaces. However, for optimum bond strength on metal parts the surface should be washed with a solvent or cleansing solution, abraded with an abrasive pad, and then rinsed with a solvent or cleansing solution. Glass surfaces should be cleaned with a commercial glass cleaner before bonding. Painted surfaces should be abraded lightly and then wiped clean.
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Application
Bondmaster's Equipment Group, has a complete line of industrial dispensing equipment to dispense the 681 in magnet bonding applications. Equipment is available to dispense the adhesive through Bondmaster's unique External Mix dispensing process. The External Mix Dispensing System is a technology that results in high performance without the use of a static mixer. This allows the use of the adhesive in high-speed production without having to change static mixers frequently. The External Mix technology also provides the user with a higher performance than conventional bead-on-bead systems.
In addition to standard equipment, Bondmaster offers custom dispensing equipment, designed for your specific application and production requirements. Contact your local Bondmaster sales representative for more equipment information.
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Mixing
Five grams each of Bondmaster 681 Part A, Part B, and mixed adhesive were enclosed in a container with a conductive copper surface. The resistance of the copper surface was measured after a 24-hour and 240- hour exposure at temperatures of 50°C (122°F) and 150oC (302°F).
Bondmaster 681 Part A & Part B should not be mixed in large quantities, as a vigorous chemical reaction will occur generating a significant amount of heat and vapors.
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Curing
Exposure to air will inhibit the cure of all acrylic adhesives. Because of this inhibition, the exposed surface of any mixed adhesive squeezed outside the bondline will remain tacky for a few hours. Only the cure of the exposed surface is inhibited, not the adhesive in the bondline.
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Clean-Up
Unreacted Part A & Part B can be cleaned up using acetone, isopropanol, or MEK.
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Fixture or Handling Strength Time Test Methods
Fixture or Handling Strength Time | Fixture-Handling Strength Time Temperature |
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0.50 to 1.00 min | 25°C |
Viscosity Test Methods
Viscosity | Temperature |
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90,000 cPs | 25°C |
13,500 cPs | 25°C |
Work / Pot Time Test Methods
Work / Pot Time | Temperature |
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0.50 min | 25°C |
Impact Strength Test Methods
Impact Strength | Substrate | Test Method |
---|---|---|
High | ||
14 psi | Steel/Steel | ASTM 950 |
Peel Strength Test Methods
Peel Strength | Substrate | Test Method |
---|---|---|
High | ||
20 to 25 piw | Steel/Steel | ASTM 1876 |
Shear Strength Test Methods
Shear Strength | Substrate | Test Method |
---|---|---|
High | ASTM D1002 | |
3,000 to 3,500 psi | Steel/Steel | ASTM D1002, Substrate failure |
2,000 psi | Ferrite/Steel | ASTM D1002, Substrate failure |
250 psi | Glass/Glass |
Shore D Hardness Test Methods
Shore D Hardness | Hardness Temperature |
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70 to 75 | 25°C |