研究了Al2O3稀释剂添加量对NiO/Al体系燃烧速度及体系产物形貌的影响,结合绝热温度的计算结果,基于Merzhanov等提出的燃烧波速公式,根据体系In(v/Tnd)-1/Ld的Arrhenius图,测定了添加Al2O3后NiO/Al体系的反应激活能。研究结果表明:对于NiO/Al体系,在一定范围内(0~5%,25%~35%,质量分数)添加Al2O3稀释剂时,体系绝热温度与燃烧速度均不发生较大变化;体系的反应过程受到压块内铝反应物传质过程的影响,高于2740K时(Al反应物沸点温度),体系的表观反应激活能为(64±14)kJ/mol,温度低于2740K时,压块内的传质过程将以毛细作用为主,体系的反应激活能为(189±15)kJ/mol。
The effects of diluting agent Al2O3 on the combustion velocity and the products microstructurc of NiO/A1 aluminothermic system were studied. Combined with the adiabatic temperature calculation, the apparent activation energy of NiO/Al system were measured by Arrhenius diagram of ln(v/Tnd )- 1/Tnd~ based on the combustion equation proposed by Merzhanov et ah The results show that in a certain range of A1203 mass fraction (0-5%, 25%-35%), the combustion velocity of NiO/Al aluminothermic system is considerable invariable. The further results show that the process of combustion is contributed to the mass transferring of Al reactant of burning compact. When the temperature above the boiling point of Al(2740 K), the apparent activation energy of NiO/Al aluminothermic system is (64±14) kJ/mol. On the contrary, that is (189±15) kJ/mol.