The effects of heat treatment and strontium （SO addition on the microstructure and mechanical properties of ADC12 alloys were investigated, and two-stage solution treatment was introduced. The results indicated that ...The effects of heat treatment and strontium （SO addition on the microstructure and mechanical properties of ADC12 alloys were investigated, and two-stage solution treatment was introduced. The results indicated that the addition of Sr obviously refined the microstructure of ADC12 alloys. When 0.05 wt% Sr was added into the alloy, the eutectic Si phase was fully modified into fine fibrous structure; a-A1 and fl-A15FeSi phases were best refined; and the eutectic AlzCu phase was modified into block-like AlzCu phase that continuously distributed at the grain boundary. The ultimate tensile strength （UTS） （270.63 MPa） and elongation （3.19%） were increased by 51.2% and 73.4% respectively compared with unmodified alloys. After the two-stage solution treatment （500 ~C, 6 h＋520 ~C, 4 h）, for 0.05 wt% Sr modified ADC12 alloys, the Si phases transformed into fine particle structure and AlzCu phases were fully dissolved. The peak hardness value of the alloys processed by the two-stage solution treatment was increased by 8.3% and 6.8% respectively compared to solution treatment at 500 ~C and 520 ~C. After the aging treatment （175 ~C, 7 h）, the hardness and UTS were increased by 38.73% and 13.96% respectively when compared with the unmodified alloy.展开更多
Abstract： Microstructure and mechanical properties of modified ultrahigh carbon （1.6%C） steels with different Mo additions （0, 0.3%, 0.5%, and 0.8%, mass fraction） were studied in their as-cast and quenched then ...Abstract： Microstructure and mechanical properties of modified ultrahigh carbon （1.6%C） steels with different Mo additions （0, 0.3%, 0.5%, and 0.8%, mass fraction） were studied in their as-cast and quenched then tempered conditions by optical microscopy, scanning electronic microscopy, X-ray diffraction and hardness and toughness tests, respectively. The results show that the continuous eutectic carbide network structure has been broken down and changed to partial isolated and finer particles embedded in matrix of as-cast alloy by modification. Carbides in both quenched and tempered specimens have been refined effectively after the addition of Mo. Specimen containing 0.5% Mo shows the finest microstructures with carbides dispersed homogeneously in martensite matrix and demonstrates highest impact toughness of 18.4 J/cm2 and hardness of 50 HRC.展开更多
Modification and characterization of natural zeolite under some various methods for hydrocracking catalyst of waste lubricant to gasoline and diesel fractions have been conducted. Natural zeolite from Klaten was activ...Modification and characterization of natural zeolite under some various methods for hydrocracking catalyst of waste lubricant to gasoline and diesel fractions have been conducted. Natural zeolite from Klaten was activated using hydrothermal treatment at temperature 500 ℃ for 6 h （produced ZAAHd）, the ZA sample was treated with hydrothermal followed by Microwave （produced ZAAHdM）, the ZA sample was treated with HCI 3 N at temperature of 90 ℃ for 30 min （produced ZAAH）, the ZAAH sample was heated in to microwave （produced ZAAHM）, the ZAAHM was treated hydrothermal （produced ZAAHMHd）, the ZAAHMHd sample was heated in to microwave （produced ZAAHMHdM）, soaking of natural zeolit activated by HCl-microwave-hydrothermal-microwave in NH4NO3 1 N which was stirred using stirer at room temperature for 24 h （produced ZAAHMHdMN） and the ZAAHMHdMN sample was heated into microwave （ZAAHMHdMNM）. The heating process by microwave was conducted at 550 watt for 15 rain. Catalyst characterization involved determination of the number of total acid sites using gravimetric method with vapour adsorption of NH3 and pyridine, catalyst crystallinity by XRD （X-ray diffraction） and TO4 （T= Si and AI） site by infra red spectrophotometer （IR）. Hydrocracking of waste lubricants oil was performed in a fixed bed reactor of stainless steel at temperature of 450 ℃, H2 flow rate of 15 mL/min., feed/catalyst ratio of 5. Liquid products of the hydrocracking were analyzed using GC （gas chromatography）. The characterization results showed that various modification of natural zeolite increased acidity and dealumination degree of the catalysts. Products of the hydrocracking were liquid, coke, and gas fractions. Liquid products consisted of gasoline fraction （C5-C12）, diesel fraction （C12-C20）, and heavy oil fraction （〉 C20）.Thc conversion of liquid products was increased with the increase of catalyst acidity. The greatest liquid product conversion was produced by the ZAAHMHdMNM catalyst, i.e., 56.80%, with selectivity towards gasoline, diesel, and heavy oil fractions was 88.37%, 8.61% and 3.02%, respectively. The increase of catalyst acidity increased the selectivity of gasoline fraction.展开更多
基金Project（51364035） supported by the National Natural Science Foundation of China Project（20133601110001） supported by the Ministry of Education Tied up with the Special Research Fund for the Doctoral Program for Higher School, China+1 种基金 Project（KJLD14003） supported by the Loading Program of Science and Technology of College of Jiangxi Province, China Project（2012-CYH-DW-XCL-002） supported by the Production and Teaching and Research Cooperation Plan of Naaachaaag Non-party Experts and Doctor, China
文摘The effects of heat treatment and strontium （SO addition on the microstructure and mechanical properties of ADC12 alloys were investigated, and two-stage solution treatment was introduced. The results indicated that the addition of Sr obviously refined the microstructure of ADC12 alloys. When 0.05 wt% Sr was added into the alloy, the eutectic Si phase was fully modified into fine fibrous structure; a-A1 and fl-A15FeSi phases were best refined; and the eutectic AlzCu phase was modified into block-like AlzCu phase that continuously distributed at the grain boundary. The ultimate tensile strength （UTS） （270.63 MPa） and elongation （3.19%） were increased by 51.2% and 73.4% respectively compared with unmodified alloys. After the two-stage solution treatment （500 ~C, 6 h＋520 ~C, 4 h）, for 0.05 wt% Sr modified ADC12 alloys, the Si phases transformed into fine particle structure and AlzCu phases were fully dissolved. The peak hardness value of the alloys processed by the two-stage solution treatment was increased by 8.3% and 6.8% respectively compared to solution treatment at 500 ~C and 520 ~C. After the aging treatment （175 ~C, 7 h）, the hardness and UTS were increased by 38.73% and 13.96% respectively when compared with the unmodified alloy.
基金the Chang Gao Advanced Materials Co.,Ltd.for the financial support
文摘Abstract： Microstructure and mechanical properties of modified ultrahigh carbon （1.6%C） steels with different Mo additions （0, 0.3%, 0.5%, and 0.8%, mass fraction） were studied in their as-cast and quenched then tempered conditions by optical microscopy, scanning electronic microscopy, X-ray diffraction and hardness and toughness tests, respectively. The results show that the continuous eutectic carbide network structure has been broken down and changed to partial isolated and finer particles embedded in matrix of as-cast alloy by modification. Carbides in both quenched and tempered specimens have been refined effectively after the addition of Mo. Specimen containing 0.5% Mo shows the finest microstructures with carbides dispersed homogeneously in martensite matrix and demonstrates highest impact toughness of 18.4 J/cm2 and hardness of 50 HRC.
文摘Modification and characterization of natural zeolite under some various methods for hydrocracking catalyst of waste lubricant to gasoline and diesel fractions have been conducted. Natural zeolite from Klaten was activated using hydrothermal treatment at temperature 500 ℃ for 6 h （produced ZAAHd）, the ZA sample was treated with hydrothermal followed by Microwave （produced ZAAHdM）, the ZA sample was treated with HCI 3 N at temperature of 90 ℃ for 30 min （produced ZAAH）, the ZAAH sample was heated in to microwave （produced ZAAHM）, the ZAAHM was treated hydrothermal （produced ZAAHMHd）, the ZAAHMHd sample was heated in to microwave （produced ZAAHMHdM）, soaking of natural zeolit activated by HCl-microwave-hydrothermal-microwave in NH4NO3 1 N which was stirred using stirer at room temperature for 24 h （produced ZAAHMHdMN） and the ZAAHMHdMN sample was heated into microwave （ZAAHMHdMNM）. The heating process by microwave was conducted at 550 watt for 15 rain. Catalyst characterization involved determination of the number of total acid sites using gravimetric method with vapour adsorption of NH3 and pyridine, catalyst crystallinity by XRD （X-ray diffraction） and TO4 （T= Si and AI） site by infra red spectrophotometer （IR）. Hydrocracking of waste lubricants oil was performed in a fixed bed reactor of stainless steel at temperature of 450 ℃, H2 flow rate of 15 mL/min., feed/catalyst ratio of 5. Liquid products of the hydrocracking were analyzed using GC （gas chromatography）. The characterization results showed that various modification of natural zeolite increased acidity and dealumination degree of the catalysts. Products of the hydrocracking were liquid, coke, and gas fractions. Liquid products consisted of gasoline fraction （C5-C12）, diesel fraction （C12-C20）, and heavy oil fraction （〉 C20）.Thc conversion of liquid products was increased with the increase of catalyst acidity. The greatest liquid product conversion was produced by the ZAAHMHdMNM catalyst, i.e., 56.80%, with selectivity towards gasoline, diesel, and heavy oil fractions was 88.37%, 8.61% and 3.02%, respectively. The increase of catalyst acidity increased the selectivity of gasoline fraction.
