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The mathematical models are developed to evaluate the ultimate tensile strength( UTS) and hardness of CNTs / Al2024 composites fabricated by high-energy ball milling. The effects of the preparation variables which are milling time,rotational speed,mass fraction of CNTs and ball to powder ratio on UST and hardness of CNTs / Al2024 composites are investigated. Based on the central composite design( CCD),a quadratic model is developed to correlate the fabrication variables to the UST and hardness. From the analysis of variance( ANOVA),the most influential factor on each experimental design response is identified. The optimum conditions for preparing CNTs / Al2024 composites are found as follows: 1. 53 h milling time,900 r / min rotational speed,mass fraction of CNTs 2. 87% and Ball to powder ratio 25 ∶ 1. The predicted maximum UST and hardness are 273.30 MPa and 261.36 HV,respectively. And the experimental values are 283.25 MPa and256.8 HV,respectively. It is indicated that the predicted UST and hardness after process optimization are found to agree satisfactory with the experimental values.
The mathematical models are developed to evaluate the ultimate tensile strength (UTS) and hardness of CNTs / Al2024 composites fabricated by high-energy ball milling. The effects of the preparation variables which are milling time, rotational speed, mass fraction of CNTs and ball to Based on the central composite design (CCD), a quadratic model is developed to correlate the fabrication variables to the UST and hardness. From the analysis of variance (ANOVA), the Most influential factor on each experimental design response was identified. The optimum conditions for preparing CNTs / Al2024 composites were found as follows: 1. 53 h milling time, 900 r / min rotational speed, mass fraction of CNTs 2. 87% and Ball to The predicted maximum UST and hardness are 273.30 MPa and 261.36 HV, respectively. And the experimental values are 283.25 MPa and 256.8 HV, respectively. It is indicated that the predicte d UST and hardness after process optimization are found to agree satisfactory with the experimental values.