Space materials radiation effects

Further insight into radiation mechanisms can be obtained by comparing different types of radiation, in particular alpha radiation, gamma (or fast electron) radiation, and ultraviolet light. Their effects are also important in such varied fields as space materials and radiological protection. 

The advent of the space age, the testing of intercontinental ballistic missiles, the use of space probes, the existence of radiation belts in outer space, and the increasing utilization of military and civilian satellites have triggered further studies on the effects of nuclear radiation on all types of materials, including expls, propints, pyrots and related materials. Nuclear radiation effects studies range from steady-state to transient environments, from ground zero to upper atmosphere levels and from underground nuclear tests to simulation techniques in the laboratory which in turn cover all phases of vulnerability and survivability... 

Nuclear, Pulsed, and Space Radiation Effects Projects , REIC Memorandum 11-C, Battelle Memorial Inst, Columbus (1963) (AD-338950) 118) H.M. Abbott, Radiation Effects on Propellants, Explosives and Related Materials An Annotated Bibliography (U) , Rpt No 6-90-63-54, Lockheed Missiles Space Co, Sunnyvale (1963) (C) (AD-3 40240) 119) Anon, Radia-... 

Additional work was performed by Gardner (Refs 92 99) on proplnts for future missions in space. A PBAA AP/Al proplnt, an aluminized double-base proplnt, and a polyurethane—AP/Al proplnt were studied as a function of Co radiation, with a dose rate of 2.54 x 10 R/hr and total doses ranging up to 1.5 x 10 R. The effects were noted on tests with the burning rate, tensile stress, elongation modules and hardness of the three materials. The PBAA proplnt withstood 1.5 X lO R. On the tensile strength, the double base and polyurethane decrease significantly at a dose of 4 x 10 R. On elongation, the double base decreased on stress at max strain after 10 R, while the polyurethane pro-pint decreased on modulus and hardness after a dose of 10 R. Estimates of the radiation effects on polymers are listed in Table 19... 

C.L. Hanks and D.J. Hamman, "Electrical Insulating Materials and Capacitors," Section 3 of Radiation Effects Design Handbook, NASA CR-1787, National Aeronautics and Space Administration, Washington, D.C. (1971). 

Areas of continuing research related to human environments in space include the effects of solar and other types of radiation on spacefering humans and their spacecraft, the availability of extraplanetary resources that could sustain human life in space and power the spacecraft, the creation of materials to protect humans in space or on other planets, realistic colonization prospects for humans on other planets or satellites, funding and management of space projects related to human environments in space, and the determination of whether living in space is a realistic option for human beings. 

Understanding the effects of ionizing radiation on the properties of plastics materials is important in nuclear engineering, space research, radiation processing, and radiation sterilization. 

The effects of the radiation flux in space on polymer materials is now of considerable importance due to the increasing use of communications satellites. Geosynchronous orbit corresponds to the second Van Allen belt of radiation, which comprises mainly electrons and protons of high energy. 

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