Physical and adhesive properties testing of adhesives (below)

(B), peeling and uneven tear strength

1. Peel strength: The tensile strength when the stress is concentrated on the edge of the test piece's glue seam. When a rigid material (such as metal) is bonded to a flexible material such as rubber or fabric, the peel strength needs to be measured.

2, peel strength and uneven tear strength test method:

2.1. Test Method for Peel Strength: The "T" 180 degree peel is also the standard "T" peel.

2.2, uneven tear strength test method:

3. Factors affecting peel strength:

3.1, stress distribution of rubber joint "line stress"

3.2. Effect of peeling angle on peeling strength The peeling strength decreases rapidly with increasing peeling angle. When the peeling angle approaches 90 degrees, the peeling strength tends to be a fixed value.

3.3 The effect of adhesive layer thickness The thicker the adhesive layer, the lower the bonding strength, but not too thin.

(III) Impact and Durability

1. Impact strength: The work done by the adhesive on the unit area under the impact load. The "T" peel test is used to test the toughness of the adhesive.

2. Durability: It is also called creep performance. It refers to the ability of the adhesive to cure and resist the effect of constant load over time.

The experimental time is longer than 103H.

d) Fatigue strength

1. Fatigue strength: Due to the cyclical alternating stress, the rubber head is fatigued and destroyed. That is, under the given conditions, the maximum stress caused by repeated application of a certain load to the rubber joint to the specified number of times, the number of cycles is 107 times.

2, factors that affect fatigue strength

2.1, fatigue strength S and fatigue life relationship: S = A-KtgN A, K is a constant.

2.2, relationship between fatigue life N and temperature: tgN = A + B / TA, B is a constant

2.3, the effect of frequency of stress changes on fatigue strength: tgN = tgb-mtgf b, m is a constant, f is the frequency

Therefore, the fatigue strength decreases with decreasing frequency.

Source: China Adhesive Network