948. A category of plastic material that is capable of softening or flowing when reheated is described as a thermoplastic. thermocure. Thermoset.
949. A potted compound repair on honeycomb can usually be made on damages less than 4 inches in diameter. 2 inches in diameter. 1 inch in diameter.
950. Composite fabric material is considered to be the strongest in what direction? Fill. Warp. Bias.
951. Composite inspections conducted by means of acoustic emission monitoring pick up the noise of corrosion or other deterioration ocurring. Analize ultrasonic signals transmitted into the parts being inspected. create sonogram pictures of the areas being inspected.
952. Composite inspections conducted by means of acoustic emission monitoring pick up the 'noise' of corrosion or other deterioration occurring. analyze ultrasonic signals transmitted into the parts being inspected. create sonogram pictures of the areas being inspected.
953. Fiberglass damage that extends completely through a laminated sandwich structure may be repaired. must be filled with resin to eliminate dangerous stress concentrations. may be filled with putty which is compatible with resin.
954. Fiberglass laminate damage not exceeding the first layer or ply can be repaired by filling with a putty consisting of a compatible resin and clean, short glass fibers. sanding the damaged area until aerodynamic smoothness is obtained. trimming the rough edges and sealing with paint.
955. Fiberglass laminate damage that extends completely through one facing and into the core cannot be repaired. requires the replacement of the damaged core and facing. can be repaired by using a typical metal facing patch.
956. One method of inspecting a laminated fiberglass structure that has been subjected to damage is to strip the damaged area of all paint and shine a strong light through the structure. use dye-penetrant inspection procedures, exposing the entire damaged area to the penetrant solution. use an eddy current probe on both sides of the damaged area.
957. One of the best ways to assure that a properly prepared batch of matrix resin has been achieved is to perform a chemical composition analysis. have mixed enough for a test sample. test the viscosity of the resin immediately after mixing.
958. Repairing advanced composites using materials and techniques traditionally used for fiberglass repairs is likely to result in restored strength and flexibility. improved wear resistance to the structure. an unairworthy repair.
959. Superficial scars, scratches, surface abrasion, or rain erosion on fiberglass laminates can generally be repaired by applying a piece of resin-impregnated glass fabric facing. one or more coats of suitable resin (room-temperature catalyzed) to the surface. a sheet of polyethylene over the abraded surface and one or more coats of resin cured with infrared heat lamps.
960. The classification for fiberglass reinforcement material that has high resistivity and is the most common is E S G.
961. The classification for high tensile strength fiberglass used in aircraft structures is E S G.
962. The length of time that a catalyzed resin will remain in a workable state is called the Shelf life. Pot life Service life Life limit.
963. The length of time that a catalyzed resin will remain in a workable state is called the Pot life. Shelf life. Service life.
964. The strength and stiffness of a properly constructed composite buildup depends primarily on A 60 percent matrix to 40 percent fiber ratio. The orientation of the plies to the load direction. The ability of the fibers to transfer stress to the matrix.
965. What is the material layer used within the vacuum bag pressure system to absorb excess resin during curing called? Bleeder. Breather. Release.
966. What precaution, if any, should be taken to prevent corrosion inside a repaired metal honeycomb structure? Prime the repair with a corrosion inhibitor and seal from the atmosphere. Paint the outside area with several coats of exterior paint. None. Honeycomb is usually made from a man-made or fibrous material which is not susceptible to corrosion.
967. When balsa wood is used to replace a damaged honeycomb core, the plug should be cut so that the grain is parallel to the skin. it is about 1/8 inch undersize to allow sufficient bonding material to be applied. the grain is perpendicular to the skin.
968. When inspecting a composite panel using the ring test/tapping method, a dull thud may indicate Less than full strength curing of the matrix. Separation of the laminates. An area of too much matrix between fiber layers.
969. When installing transparent plastic enclosures which are retained by bolts extending through the plastic material and self-locking nuts, the nuts should be: tightened to a firm fit, then backed off one full turn tightened to a firm fit, plus one full turn. tightened to a firm fit.
970. When making repairs to fiberglass, cleaning of the area to be repaired is essential for a good bond. The final cleaning should be made using MEK (methyl ethyl ketone). soap, water, and a scrub brush. a thixotropic agent.
971. When necessary, what type of cutting fluid is usually acceptable for machining composite laminates? Water soluble oil. Water displacing oil. Water only.
972. When repairing large, flat surfaces with polyester resins, warping of the surface is likely to occur. One method of reducing the amount of warpage is to add an extra amount of catalyst to the resin. use short strips of fiberglass in the bonded repair. use less catalyst than normal so the repair will be more flexible.
973. When repairing puncture-type damage of a metal faced laminated honeycomb panel, the edges of the doubler should be tapered to two times the thickness of the metal. 100 times the thickness of the metal. whatever is desired for a neat, clean appearance. .
974. Which fiber to resin (percent) ratio for advanced composite wet lay-ups is generally considered the best for strength? 40:60 2,118055556 2,527777778.
975. Which is an identifying characteristic of acrylic plastics? Zinc chloride will have no effect. Acrylic has a yellowish tint when viewed from the edge. Acetone will soften plastic, but will not change its color.
976. Which of the following are generally characteristic of aramid fiber (Kevlar) composites? Stiffness Corrosive effect in contact with aluminun. flexibility and high tensile strength Ability to conduit electricity.
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