Table F-3. Summary of Joint Evaluation Tests 



Capsule 

 No. 



Adhesive Used 



No. of 



Test 

 Specimens" 



NCEL's 

 Specified 

 Minimum 



Tensile 



Strength 



(psi) 



Tensile Strength (psi)" 



Maximum 



Minimum 



Average 



1 

 2 

 3 



PS-18 (modified 

 by Swedlow) 



SS-6217 (developed 

 by Swedlow) 



SS-6217 (developed 

 by Swedlow) 



16 

 16 

 12 



4,000 

 4,000 

 4,000 



9,300 

 7,970 



8,640 



7,250 

 6,340 

 6,860 



8,580 

 7,150 

 8,300 



The test specimens for each capsule were 0.750 in. thick by 

 0.500 in. wide. The 0.1 25-in.-wide joint was located in the 

 center of the test specimen length. Overall length of specimens 

 was 8.125 in. 



' The tensile strength of joints in prototype capsule was by 

 comparison 9,220-psi maximum, 5,680-psi minimum, and 

 7,350-psi average. 



The tensile strength of all the joint test coupons (Table F-3) was 

 found to be in excess of the specified minimum 4,000 psi, and thus 

 acceptable. As can be seen from Table F-3, the tensile strength range of 

 6,300 to 9,800 psi of the joints in capsules 1 , 2, and 3 was approximately 

 the same as for the prototype capsule (NEMO 0), for which the tensile 

 strength of the joints was in the 5,680 to 9,200-psi range. 



Metallic Closures 



The quality control for the polar metal plates (Figure F-3) consisted 

 of material control, dimensional inspection, visual finish inspection, and 

 structural integrity testing. The material quality control consisted of 

 notarized invoices from the supplier certifying the steel stock to be annealed 

 type 4130 steel (MIL-S-18729C) with Brinell hardness in the 163-170 range. 

 The dimensional control consisted of checking the dimensions of machined 

 steel parts for conformance to the drawings. After electroplating the steel 

 parts with cadmium without any brightener, the parts were visually inspected 

 for appearance and quality. If the dimensional check and the visual inspec- 

 tion showed the parts to be satisfactory, they were accepted for mounting 

 in the acrylic plastic capsules. 



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