Lec19 adhesives

Question 1

adhesives

Answer 1

are very strong, material around them normally fails first

Question 2

applications

Answer 2

many applications

Question 3

anaerobics adhesives

Answer 3

activate due to absence of air causes curing to take place

Question 4

Types of adhesive

Answer 4

epoxy
cyanoacrylate
hybrid
sealants

Question 5

Methods of glue drying

Answer 5

UV

anaerboic

Question 6

adhesives are strong and weak under what type of loads

Answer 6

strong under shear load

weak under peal load

Question 7

to maximise joint strength increase overlap length or joint width

Answer 7

increase joint width improves joint strength, increasing overlap does not have the same affect

Question 8

UV adhesives adv

Answer 8

very fast drying time
can position part and then once happy use UV to set
BUT do need UV lighting

Question 9

Epoxy

Answer 9

two parts - resin and hardener

cure time 5 min or 4 hours slower the cure stronger the bond

Question 10

what surface prep is require

Answer 10

need to clean surfaces - dont want to glue the dirt and grime together

Question 11

To toughen adhesives can add what

Answer 11

rubber will increase strength against peel loads

Question 12

Cyanoacrylate

Answer 12

easy to dispense

quickly cures so can achieve 60% strength after 1 minute 100% after 24 hours