The products have been tested using the following parameters:
The Durometer is used for the Hardness testing with the higher readings the hardest products. The Shore D ratings for the harder products, the Shore A, for the softer elastomers and plastics, and the Shore 00 for very soft rubbers and gels. Hardness was considered ‘the resistance of a material to permanent indentation’ by Albert Ferdinand Shore in the 1920’s, who developed The Durometer to measure hardness, and to develop a scale to relate the findings. Originally the Durometer was a mechanical machine that launched domed or pointed ‘indenters’, now it is a hand-held electronic device, with immediate results.
The Tensile Strength is a measurement of the maximum Tensile Stress, or Stretch, required when acting on a product to make it fail, or tear, and is measured in force per unit of cross-sectional area, eg. N/
sq.mm. or psi. Steel bar A36 ASTM, for example has Tensile strength 399.90 N/
sq.mm. (58,000 psi,) Aluminium 310.26 N/
sq.mm. (45,000 psi), Cast Iron 199.95 N/
sq.mm. (29,000 psi), and Brass 248.21 N/
sq.mm. (36,000 psi).
Compressive Strength, conversely, is ‘The maximum compressive stress that, under gradually applied load, a given solid material will sustain without fracture’, Mild Steel for example, has a compressive strength of 250 N/
sq.mm. (36,250 psi), at room temperature, but at -60ºC becomes brittle, Stainless Steel grade 316 (UNS S31600) 170- 310 N/
sq.mm. (24,650-44,950 psi.), Aluminium depending on alloys and grain quality, can have a rating of approximately 280 N/
sq.mm. (40,600 psi), at -200ºC, or as little as 50.43 N/
sq.mm. (7,312 psi) at 371ºC.
Also used to measure Compressive Strength is the Young’s Modulus of Elasticity, named after the 19th century English Physician and Physicist Thomas Young. The stress measured is specifically lengthwise stress, also taken into consideration
46 | The Report • September 2017 • Issue 81
Torn aluminium hull, drilled, ground clean and rebuilt with 1016 Ceramic Cream, and protected with coats of 1020 White Coating
Stainless Steel propellor shaft pitting rebuilt with 1010 Cream Repair at bearing
is the ability to recover its’ original dimensions. The values change relative to the orientation and temperature in most materials, and lessen mostly after each test. Results for The Modulus show that Nylon has a value of 4.2 N/
sq.mm. (290-580 psi), GRP matrix 36.08 N/
sq.mm. (2,490 psi), Carbon Fibre matrix 63.4-105.07 N/
sq.mm. (4,350-7250 psi), Aluminium 144.93 N/
sq.mm. (10,000 psi), Brass 262.32 N/
sq.mm (18,100 psi), and Stainless Steel 316 up to 420.29 N/
sq.mm. (29,000 psi).
The tests are overseen by independent bodies, DIN is the Deutsches Institut fur Normung, ASTM is American
Standard Test Method, and ISO the International Standards Organisation in Switzerland.
These values are extremely useful when deciding which of the product range is applicable to the specific job-in-hand, and with sufficient knowledge and experience allows for successful solutions.
Hopefully, this information will be useful when assessing applications, and the possibilities that Epoxides provide.
Product or application advice or information is available at wencon.
baleares@outlook.com, and all specifications can be found at
www.wencon.com.
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84
