5.1 Test Specification and Procedures
Practice B consists of exposing the laminate coupons to the chemical reagents while being held at 1% strain in a fixture device. At the completion of the seven-day exposure period each coupon was visually evaluated and mechanically tested in accordance with ASTM D790 to determine if the stressed chemically exposed laminates mechanical properties changed. Test results were compared with the water control of the immersed tests.
5.2 Test Laminate coupons
Test laminate coupons for the astm d543 Practice B testing were cut from Saint-Gobain Technical Fabrics Plates 12, 20, 21, and 23. All test laminate coupons measured approximately 100 mm in length by 25 mm in width and 5 mm in depth. Dimension measurements were measured using a digital calliper accurate to ±0.005 mm. While measuring the laminate coupons it was noted that the specimen edges were at a slight angle with respect to the depth of the material. This slight angle resulted in laminate coupons being moderately wider on one face (top compared to bottom). This slight angle is a characteristic of the JetCut process.
A total of 30 laminate coupons were tested: three laminate coupons for each of the 10 chemical reagents.
5.3 Test Equipment
Each laminate coupon was placed in a strain fixture device and strained to 1 % in bending. The strain fixtures and laminate coupons were placed in Plastic containers filled with chemical reagent. Chemical reagent levels in the containers were maintained so that the coupons were fully submerged over the seven-day soaking period.
The strain fixture device was designed so the laminate coupon specimen would maintain 1% bending strain condition during the seven-day immersion period. The device uses a three point bending design with coupon contact dimensions similar to those used in the D790 test. Figure 5.1 shows a schematic of the strain device in a three-dimensional view while Figure 5.2 shows the device in a side and front view.
A stainless steal screw was used in conjunction with a quarter inch diameter pin to apply 1% strain across the mid-section of the coupon. Prior to ASTM D543 testing specimen coupons were tested in the device using a strain gauge bonded to the bottom of the specimen coupon. This was done to determine how many rotations of the screw were required to achieve 1% bending strain in the coupon outer fibre. It was found that two and half rotations produced the desired strain and that the strain level remained constant over a seven-day period.
5.4 Test Results
Testing was performed from July 4, 2001 to August 20, 2001. In total 30 laminate coupons were tested. The laminate coupons were named using the labelling scheme described in Section 3.4 of this report. Figure 5.3 illustrates the pre-test conditions of the ASTM D543 Procedure B test laminate coupons.
Tables 5.1 and 5.2 present the results of the flexure testing on the chemically exposed laminate coupons for the ASTM D543 Practice B test. The data sheets and data plots for each test are located in the CD attached to this report.
Figure 5.4 shows the normalized flexural yield stress and yield strain for laminate coupons exposed to chemical reagents then tested in accordance with ASTM D790 (three point flexure). February 9, 2001 non-exposed minimum flexural stress and strain tests data was used to normalize the test data. Non-exposed minimum values were used due to the variation in test results illustrated in Figure 1.1.
Figure 5.4 Average chemical exposed laminate coupon yield stress and yield strain data after exposure under 1% bending strain normalized using February 9, 2001 minimum non-exposed after ASTM D790 three-point flexure test data.
Based on Figure 5.4 the following conclusions can be drawn.
1. All chemical reagents appear to decrease the laminates flexural yield stress and yield strain.
2. Water, 1% Nitric Acid, 1% Ferric Chloride, and 0.1% soap reduced the flexural yield stress by less than 10% and the yield strain by 12 to 24%.
3. 5% Ammonium Hydroxide and 20% Sulphuric acid reduced the flexural yield stress by 22 and 26% respectively and the yield strain by 27 and 15%, respectively.
4. 0.1% detergent reduced the flexural yield stress by 33% and the yield strain by 16%.
5. 5% Sodium Hydroxide reduced the flexural yield stress by 43% and the yield strain by 4%. Thus, 5% Sodium Hydroxide appears to significantly reduce the laminate flexural modulus.
6. BOD greater than 700 PPM reduced the flexural yield stress by 50% while reducing the yield strain by 1%. Thus, BOD greater than 700PPM appears to significantly reduce the laminate flexural modulus.
Based on Figure 5.4 the following conclusions can be drawn.
1. All chemical reagents appear to decrease the laminates flexural yield stress and yield strain.
2. Water, 1% Nitric Acid, 1% Ferric Chloride, and 0.1% soap reduced the flexural yield stress by less than 10% and the yield strain by 12 to 24%.
3. 5% Ammonium Hydroxide and 20% Sulphuric acid reduced the flexural yield stress by 22 and 26% respectively and the yield strain by 27 and 15%, respectively.
4. 0.1% detergent reduced the flexural yield stress by 33% and the yield strain by 16%.
5. 5% Sodium Hydroxide reduced the flexural yield stress by 43% and the yield strain by 4%. Thus, 5% Sodium Hydroxide appears to significantly reduce the laminate flexural modulus.
6. BOD greater than 700 PPM reduced the flexural yield stress by 50% while reducing the yield strain by 1%. Thus, BOD greater than 700PPM appears to significantly reduce the laminate flexural modulus.
Visual examination of a non-tested coupons cut from Plate 12 revealed that the coupon had an inherent plane of weakness in the middle of the test coupon (Figure 5.5). This coupon was discarded and was not used in the study. Since two of the three BOD test coupons were cut from Plate 12 (12_10a and 12_10c) inherent flaws in the test specimen prior to immersion in the chemical reagents could have resulted in the low flexural yield stress results. Further testing is required to verify that BOD greater than 700 PPM significantly reduces the laminate flexural yield stress and flexural modulus.
Figure 5.6 indicates that coupons exposed to BOD greater than 700 PPM are lower than the Phase I minimum limit. It should also be noted that two of the coupons (1 l-10b and 12-c) show much higher stress-strain response than 12-10a. Possible reasons for the lower response of coupon 12-10a are the influence of BOD or a flaw in the test coupon cut from Plate 12. If the low stress-strain response was due to a flaw in the coupon and not BOD then 50% flexural yield stress reduction shown in Figure 5.4 may not be realistic. Further testing is required to confirm the influence of BOD reduction on the coupon flexible yield stress.
Figures 5.7 and 5.8 shows that, 5% Sodium Hydroxide and 0.1% Detergent test coupons have a significantly lower yield stress than the Phase I minimum limit. Unlike the BOD test coupons three-test coupon show relatively consistent stress-strain response. This would suggest that 5% Sodium Hydroxide and 0.1% Detergent do lower the specimen flexible yield stress.
Figure 5.9 shows that one test coupon (20-8a) stress-strain response is similar to the Phase I maximum response while the other two coupons (20-8b and 20-8c) show a stress-strain response that is significantly lower than Phase I minimum limit. Possible reasons for the lower response are influence of 0.1% soap on the yield stress or a flaw in the test coupon cut from Plate 20. Further testing is required to confirm whether 0.1% soap reduces the coupon flexural yield stress.
6.0 SUMMARY
Saint-Gobain Technical Fabrics of St. Catherines provided laminate coupons to CATT representatives at the University of Waterloo, Waterloo, Ontario, in January of 2001. ASTM D543 test for evaluating the resistance of laminate product in various chemical reagents were performed at the University of Waterloo.
ASTM D543 Practice A - Procedure I: Weight and Dimensions Changes, test results indicate that the laminate product had no significant visible appearance changes after exposure to the chemicals reagent and that weight and depth changes are greater than width and length changes. All weight and dimension changes were less than 0.5%. Five percent Ammonium Hydroxide showed the greatest change (3.2%) in weight and depth. ASTM D543 Practice A - Procedure II: Mechanical Property Changes, test results indicate that immersion of test coupons in the chemical reagents, except 20% Sulphuric acid, reduces the laminate flexural yield stress and strain. 20% Sulphuric Acid appears to increase the flexural yield stress by 8% and decrease the flexural yield strain by 5%. Water and 1% Sodium Hypochloride appears to decrease the laminate flexural yield stress and strain by less than 10 percent. 1% Ferric Chloride, 5% Ammonium Hydroxide, and 5% Sodium Hydroxide show a 11 to 15% decrease in the laminate flexural yield stress and 10% decrease in flexural strain. 1% Nitric Acid and 0.1% Detergent show a 18 and 14% decrease the laminates flexural strength respectively and a 13 and 21% decrease in flexural strain respectively. 0.1% Soap and BOD greater than 700 PPM appears tosignificantly lower the flexural yield stress by 31 and 63% respectively and decrease the flexural yield strain by 14 and 10% respectively. Thus, 0.1% Soap and BOD greater than 700 PPM appear to significantly reduce the laminate flexural modulus.
The depth of BOD test coupons was significantly greater than the other chemical test coupons. The influence of coupon thickness on the flexural yield stress is not known at this time.
ASTM D543 Practice B - Mechanical Stress & Reagent Exposure, test results indicate that all chemicals appear to reduce the flexural yield stress of the test coupons. Water, 1% Nitric Acid, 1% Ferric Chloride, and 0.1% Soap reduced the flexural yield stress by less than 10% and the yield strain by 12 to 24%. 5% Ammonium Hydroxide and 20% Sulphuric acid reduced the flexural yield stress by 22 and 26% respectively and the yield strain by 27 and 15%. 0.1% detergent reduced the flexural yield stress by 33% and the yield strain by 16%. 5% Sodium Hydroxide reduced the flexural yield stress by 43% and the yield strain 4%. BOD greater than 700 PPM reduced the flexural yield stress by 50% while reducing the yield strain by 1%.
Based on the flexural testing 5% Sodium Hydroxide, 20% Sulphuric acid, 0.1% Soap, 0.1% Detergent, and BOD greater than 700 PPM appear to significantly reduce the laminate flexural modulus. Of these chemicals only BOD greater than 700PPM and 0.1% Soap showed a significant decrease in both the astm d543 Practice B - Mechanical Stress & Reagent Exposure and Practice A - Procedure II: Mechanical Property Changes.
BOD coupons were taken from Plates 12 and 11. Variations in test coupon depth indicate that these test plates had greater variation in depth across the plate than the other test plates. The low flexural yield stress results from Plates 11 and 12 could be due to the greater test specimen depth or inherent flaws in the test coupons (Figure 5.5). Further testing is required to verify that BOD greater than 700 PPM significantly reduces the laminate flexural yield stress and flexural modulus. Variations in the stress-strain response of coupons after immersion in 0.1% Soap indicates that the low yield stress results might be due to plate flaws and not due to submersion in the chemical reagents. Further testing is required to determine if 0.1 % Soap does reduce the laminate flexural modulus.Details to know more click here http://ussewer.com
Saint-Gobain Technical Fabrics of St. Catherines provided laminate coupons to CATT representatives at the University of Waterloo, Waterloo, Ontario, in January of 2001. ASTM D543 test for evaluating the resistance of laminate product in various chemical reagents were performed at the University of Waterloo.
ASTM D543 Practice A - Procedure I: Weight and Dimensions Changes, test results indicate that the laminate product had no significant visible appearance changes after exposure to the chemicals reagent and that weight and depth changes are greater than width and length changes. All weight and dimension changes were less than 0.5%. Five percent Ammonium Hydroxide showed the greatest change (3.2%) in weight and depth. ASTM D543 Practice A - Procedure II: Mechanical Property Changes, test results indicate that immersion of test coupons in the chemical reagents, except 20% Sulphuric acid, reduces the laminate flexural yield stress and strain. 20% Sulphuric Acid appears to increase the flexural yield stress by 8% and decrease the flexural yield strain by 5%. Water and 1% Sodium Hypochloride appears to decrease the laminate flexural yield stress and strain by less than 10 percent. 1% Ferric Chloride, 5% Ammonium Hydroxide, and 5% Sodium Hydroxide show a 11 to 15% decrease in the laminate flexural yield stress and 10% decrease in flexural strain. 1% Nitric Acid and 0.1% Detergent show a 18 and 14% decrease the laminates flexural strength respectively and a 13 and 21% decrease in flexural strain respectively. 0.1% Soap and BOD greater than 700 PPM appears tosignificantly lower the flexural yield stress by 31 and 63% respectively and decrease the flexural yield strain by 14 and 10% respectively. Thus, 0.1% Soap and BOD greater than 700 PPM appear to significantly reduce the laminate flexural modulus.
The depth of BOD test coupons was significantly greater than the other chemical test coupons. The influence of coupon thickness on the flexural yield stress is not known at this time.
ASTM D543 Practice B - Mechanical Stress & Reagent Exposure, test results indicate that all chemicals appear to reduce the flexural yield stress of the test coupons. Water, 1% Nitric Acid, 1% Ferric Chloride, and 0.1% Soap reduced the flexural yield stress by less than 10% and the yield strain by 12 to 24%. 5% Ammonium Hydroxide and 20% Sulphuric acid reduced the flexural yield stress by 22 and 26% respectively and the yield strain by 27 and 15%. 0.1% detergent reduced the flexural yield stress by 33% and the yield strain by 16%. 5% Sodium Hydroxide reduced the flexural yield stress by 43% and the yield strain 4%. BOD greater than 700 PPM reduced the flexural yield stress by 50% while reducing the yield strain by 1%.
Based on the flexural testing 5% Sodium Hydroxide, 20% Sulphuric acid, 0.1% Soap, 0.1% Detergent, and BOD greater than 700 PPM appear to significantly reduce the laminate flexural modulus. Of these chemicals only BOD greater than 700PPM and 0.1% Soap showed a significant decrease in both the astm d543 Practice B - Mechanical Stress & Reagent Exposure and Practice A - Procedure II: Mechanical Property Changes.
BOD coupons were taken from Plates 12 and 11. Variations in test coupon depth indicate that these test plates had greater variation in depth across the plate than the other test plates. The low flexural yield stress results from Plates 11 and 12 could be due to the greater test specimen depth or inherent flaws in the test coupons (Figure 5.5). Further testing is required to verify that BOD greater than 700 PPM significantly reduces the laminate flexural yield stress and flexural modulus. Variations in the stress-strain response of coupons after immersion in 0.1% Soap indicates that the low yield stress results might be due to plate flaws and not due to submersion in the chemical reagents. Further testing is required to determine if 0.1 % Soap does reduce the laminate flexural modulus.Details to know more click here http://ussewer.com
