Author: K. Nguyen
Publisher:
ISBN:
Category :
Languages : en
Pages : 9
Book Description
An experimental study was undertaken to investigate the ignition phenomena of 6061 aluminum alloy as a function of oxygen pressure. Cylindrical aluminum alloy specimens were ignited in a pure oxygen environment by a focused cw CO2 laser beam. To study the effect of oxygen pressure on the surface temperature at ignition of 6061 aluminum alloy, the experiments were conducted at oxygen pressures ranging from 0.084 to 2.413 MPa. The temperature history of the entire upper surface of the specimen and of a 0.5 mm diameter spot located initially at the center of the specimen top surface was recorded by using a commercial two-color ratio pyrometer and a fast-response, narrow-band, two-color pyrometer. Mass, brightness, and interior temperatures, for certain experiments were also recorded throughout the experiment. The results show that the surface temperatures at ignition of the alloy obtained from the temperature curves are below the melting temperature of the aluminum oxide and are slightly dependent on oxygen pressure. The data indicate that the ignition mechanism is complex and probably composed of several phenomena acting both separately and in conjunction with each other.
Ignition Phenomena of Bulk Aluminum Alloy as a Function of Oxygen Pressure
Author: K. Nguyen
Publisher:
ISBN:
Category :
Languages : en
Pages : 9
Book Description
An experimental study was undertaken to investigate the ignition phenomena of 6061 aluminum alloy as a function of oxygen pressure. Cylindrical aluminum alloy specimens were ignited in a pure oxygen environment by a focused cw CO2 laser beam. To study the effect of oxygen pressure on the surface temperature at ignition of 6061 aluminum alloy, the experiments were conducted at oxygen pressures ranging from 0.084 to 2.413 MPa. The temperature history of the entire upper surface of the specimen and of a 0.5 mm diameter spot located initially at the center of the specimen top surface was recorded by using a commercial two-color ratio pyrometer and a fast-response, narrow-band, two-color pyrometer. Mass, brightness, and interior temperatures, for certain experiments were also recorded throughout the experiment. The results show that the surface temperatures at ignition of the alloy obtained from the temperature curves are below the melting temperature of the aluminum oxide and are slightly dependent on oxygen pressure. The data indicate that the ignition mechanism is complex and probably composed of several phenomena acting both separately and in conjunction with each other.
Publisher:
ISBN:
Category :
Languages : en
Pages : 9
Book Description
An experimental study was undertaken to investigate the ignition phenomena of 6061 aluminum alloy as a function of oxygen pressure. Cylindrical aluminum alloy specimens were ignited in a pure oxygen environment by a focused cw CO2 laser beam. To study the effect of oxygen pressure on the surface temperature at ignition of 6061 aluminum alloy, the experiments were conducted at oxygen pressures ranging from 0.084 to 2.413 MPa. The temperature history of the entire upper surface of the specimen and of a 0.5 mm diameter spot located initially at the center of the specimen top surface was recorded by using a commercial two-color ratio pyrometer and a fast-response, narrow-band, two-color pyrometer. Mass, brightness, and interior temperatures, for certain experiments were also recorded throughout the experiment. The results show that the surface temperatures at ignition of the alloy obtained from the temperature curves are below the melting temperature of the aluminum oxide and are slightly dependent on oxygen pressure. The data indicate that the ignition mechanism is complex and probably composed of several phenomena acting both separately and in conjunction with each other.
Scientific and Technical Aerospace Reports
Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 656
Book Description
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 656
Book Description
Energy Research Abstracts
Author:
Publisher:
ISBN:
Category : Power resources
Languages : en
Pages : 672
Book Description
Publisher:
ISBN:
Category : Power resources
Languages : en
Pages : 672
Book Description
Publications of the National Bureau of Standards ... Catalog
Author: United States. National Bureau of Standards
Publisher:
ISBN:
Category :
Languages : en
Pages : 404
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 404
Book Description
Government Reports Announcements & Index
Author:
Publisher:
ISBN:
Category : Government publications
Languages : en
Pages : 1336
Book Description
Publisher:
ISBN:
Category : Government publications
Languages : en
Pages : 1336
Book Description
Publications of the National Institute of Standards and Technology ... Catalog
Author: National Institute of Standards and Technology (U.S.)
Publisher:
ISBN:
Category :
Languages : en
Pages : 406
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 406
Book Description
Heat Transfer, 1986: General papers
Author: Chang L. Tien
Publisher:
ISBN:
Category : Heat
Languages : en
Pages : 600
Book Description
Publisher:
ISBN:
Category : Heat
Languages : en
Pages : 600
Book Description
Corrosion Abstracts
Author:
Publisher:
ISBN:
Category : Corrosion and anti-corrosives
Languages : en
Pages : 722
Book Description
Publisher:
ISBN:
Category : Corrosion and anti-corrosives
Languages : en
Pages : 722
Book Description
Heat Transfer 1986
Author: Chang L. Tien
Publisher: CRC Press
ISBN: 9780891165590
Category : Heat
Languages : en
Pages : 600
Book Description
Publisher: CRC Press
ISBN: 9780891165590
Category : Heat
Languages : en
Pages : 600
Book Description
Ignition Phenomena and Controlled Firing of Reaction-bonded Aluminum Oxide
Author: Matthew James Watson
Publisher:
ISBN:
Category : Aluminum oxide
Languages : en
Pages : 392
Book Description
The ignition phenomena that can occur during the reaction-bonding of aluminum oxide is investigated. It is experimentally characterized through measurements of the combustion temperature and the velocity of the ignition front. One- and two-dimensional, transient, simultaneous material and energy balances are used to model the phenomena in a cylindrical geometry. The models are used to predict the aluminum concentration, oxygen concentration, and temperature distributions as a function of time during ignition. Thermal explosion analysis is utilized to predict the conditions under which samples will ignite, and to calculate furnace temperature programs that will avoid ignition. The aluminum concentration and temperature distributions are used to estimate the elastic stresses that are developed during ignition. Feedback control is applied to the reaction-bonded aluminum oxide system with great success. The heating rate is adjusted automatically based on the reaction rate, measured through differential thermogravimetry. Adjusting the furnace temperature in this way is more reliable and allows the sample to react in a slow and controlled manner, avoiding ignition and cracking altogether. Criteria based on heat transfer and oxygen diffusion considerations are developed to determine the reaction rate set-point, and simplify the process of reaction-bonding considerably.
Publisher:
ISBN:
Category : Aluminum oxide
Languages : en
Pages : 392
Book Description
The ignition phenomena that can occur during the reaction-bonding of aluminum oxide is investigated. It is experimentally characterized through measurements of the combustion temperature and the velocity of the ignition front. One- and two-dimensional, transient, simultaneous material and energy balances are used to model the phenomena in a cylindrical geometry. The models are used to predict the aluminum concentration, oxygen concentration, and temperature distributions as a function of time during ignition. Thermal explosion analysis is utilized to predict the conditions under which samples will ignite, and to calculate furnace temperature programs that will avoid ignition. The aluminum concentration and temperature distributions are used to estimate the elastic stresses that are developed during ignition. Feedback control is applied to the reaction-bonded aluminum oxide system with great success. The heating rate is adjusted automatically based on the reaction rate, measured through differential thermogravimetry. Adjusting the furnace temperature in this way is more reliable and allows the sample to react in a slow and controlled manner, avoiding ignition and cracking altogether. Criteria based on heat transfer and oxygen diffusion considerations are developed to determine the reaction rate set-point, and simplify the process of reaction-bonding considerably.