Preparation of ammonium nitrate/ammonium perchlorate-based solid propellant for combustion control by N2O supply

N2O供給により燃焼をON/OFF制御できる非自律燃焼性(非自燃性)固体推進薬の調製を試み，その燃焼性を調査した．本研究では，スプレードライにより防湿処理を施した硝酸アンモニウム(AN)と過塩素酸アンモニウム(AP)を酸化剤とし，末端水酸基ポリブタジエン(HTPB)をバインダとした固体推進薬を調製した．HTPBを23.5 wt%とし，酸化剤中のAN/AP比を40/60，50/50，60/40 とした推進薬についてN2雰囲気0.3-6.0 MPa で燃焼試験を行ったところ，AN/AP=40/60 はすべての圧力範囲で燃焼が完結したが，50/50 および60/40 では0.5-0.7 MPa 以下で着火しなかった．これら2 種類の推進薬は，N2O供給下，0.3 MPa での燃焼試験では燃焼が持続し，N2O供給を止めると燃焼が停止したため，本実験で調製したAN/AP 系推進薬はN2O供給により燃焼をON/OFF制御できる可能性が示唆された．
In this study, in an attempt to prepare propellants capable of on/off control of combustion by oxidizing gas supply, we prepared incombustible propellants in a N2 atmosphere composed of moisture-proof ammonium nitrate (AN) prepared by spray drying and ammonium perchlorate (AP) as oxidizers and hydroxyl-terminated polybutadiene (HTPB) as a fuel, and investigated their combustibility by N2O supply. The burning tests performed under a N2 atmosphere for the propellants having different AN/AP mass ratios (AN/AP = 40/60, 50/50, and 60/40) with 23.5 wt% HTPB revealed that the AN/AP=50/50 and 60/40 samples did not ignite under pressures less than 0.5-0.7 MPa, whereas the AN/AP=40/60 sample burned under the entire tested pressure range (0.3-6.0 MPa). Moreover, it was confirmed that the AN/AP=50/50 and 60/40 samples stably burned under N2O supply at 0.3 MPa. However, when the N2O supply was stopped, their combustion was interrupted with a little time delay, suggesting that combustion of the prepared propellants can be controlled by regulating the N2O supply.
形態: カラー図版あり
Physical characteristics: Original contains color illustrations
資料番号: AA1830031008
レポート番号: JAXA-RR-18-006