MetallPub Date : 2013-10-01DOI: 10.1002/9781118787922.CH1
E. Hornbogen
{"title":"Precipitation Hardening ‐ The Oldest Nanotechnology","authors":"E. Hornbogen","doi":"10.1002/9781118787922.CH1","DOIUrl":"https://doi.org/10.1002/9781118787922.CH1","url":null,"abstract":"Precipitation hardening of aluminum was discovered about 100 years ago by Dr. Alfred Wilm [1,2]. Using aluminum alloys as example a survey is given on mechanism and limits of precipitation hardening. It is discussed how hard, nanometer-size particles (nanos, greek, the dwarf) can form as an ultra fine dispersoid. A simple example for optimum conditions is provided by diamond cubic particles (Si, Ge) in the f.c.c. Al-Matrix. The role of a sequence from more to less metastable phases is discussed, as well as the effects of additional (and trace) alloying elements. The amount of precipitation hardening is limited, besides by the volume fraction of particles, by their strength. This in turn determines the critical diameter above which the transition from passing to by-passing by dislocations takes place. Simple models for the calculation of this microstructural parameter are discussed. From combinations of precipitation hardening with other hardening mechanisms the limits for ultra high strengths are defined.","PeriodicalId":35782,"journal":{"name":"Metall","volume":"24 1","pages":"1-11"},"PeriodicalIF":0.0,"publicationDate":"2013-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82180597","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
MetallPub Date : 2008-01-01DOI: 10.1002/9783527627110.ch13
S. Kalinichenka, H. Weidmüller, T. Weissgärber, B. Kieback, C. Kirchberger, H. Kau
{"title":"Neuartige kupfer-PCM-Verbundwerkstoffe für Anwendungen im Bereich des thermischen Managements","authors":"S. Kalinichenka, H. Weidmüller, T. Weissgärber, B. Kieback, C. Kirchberger, H. Kau","doi":"10.1002/9783527627110.ch13","DOIUrl":"https://doi.org/10.1002/9783527627110.ch13","url":null,"abstract":"","PeriodicalId":35782,"journal":{"name":"Metall","volume":"1 1","pages":"641-646"},"PeriodicalIF":0.0,"publicationDate":"2008-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83420422","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
MetallPub Date : 2006-04-21DOI: 10.1002/3527607331.CH48
M. Brey
{"title":"Horizontal Continuous Casting of Copper Alloy Billets","authors":"M. Brey","doi":"10.1002/3527607331.CH48","DOIUrl":"https://doi.org/10.1002/3527607331.CH48","url":null,"abstract":"The steadily growing demand for copper and copper alloy products and the increasing cost pressure on metal manufacturers in a global competition demand for an increase of productivity and plant availability, optimization of product quality and quality assurance and a cut of production costs. These demands represent a particular challenge to the casting process, usually the first step in the production chain. In order to meet or even exceed the above-mentioned demands it is obligatory to apply equipment, which incorporates the most economic and efficient technology. Although the horizontal continuous casting process is well established for the production of brass billets, it offers sufficient chances for further development. These chances are the drive for the research and development activities of Demag Technica, a subsidiary of SMS Meer GmbH. It is an ISO 9000 certified manufacturer of continuous casting equipment predominately for the copper and copper alloy industry. Nowadays horizontal continuous casting plants are capable of producing billets up to 400 mm diameter in single or multiple strand operation. It is realized however that the tendency, particularly for leaded brasses, goes towards casting larger billet diameters and multiple strand operation. With the example of two recently supplied horizontal continuous casting plants it is outlined how the developments of Demag Technica contribute to the raise of competitiveness of its customers. .","PeriodicalId":35782,"journal":{"name":"Metall","volume":"9 1","pages":"323-332"},"PeriodicalIF":0.0,"publicationDate":"2006-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85261819","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
MetallPub Date : 2006-03-01DOI: 10.21608/jesaun.2006.110475
A. A. Omar, A. Kandil
{"title":"The corrosion behaviour of Zn-4Al (AC43A) and Sip(Zn-4Al) composites in an artificial sea water","authors":"A. A. Omar, A. Kandil","doi":"10.21608/jesaun.2006.110475","DOIUrl":"https://doi.org/10.21608/jesaun.2006.110475","url":null,"abstract":"The corrosion behavior of the cast Zn-4Al and Si/ (Zn-4Al) alloys when attacked by 3.5 % NaCl solution at different temperatures, 31, 40, 50, and 60 °C was investigated. The Tafel intercept logarithmic polarization methods were utilized for determining the corrosion parameters. Some corrosion kinetic and mechanistic parameters hare been studied in the absence and presence of various concentrations of K 2 CrO 4 . The study indicated that the percentage inhibition efficiency increased with the increase of the inhibitor concentration and decreased with the increase of solution temperature. The activation energy of corrosion increased with the increase of both the corrosion rate and temperature. The addition of Si particles into Zn-4Al can greatly improve the corrosion resistance and has a significant effect on the Tafel polarization measurements. The corrosion resistance increases with increasing the volume fraction of Si-Particles.","PeriodicalId":35782,"journal":{"name":"Metall","volume":"36 1","pages":"466-470"},"PeriodicalIF":0.0,"publicationDate":"2006-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77235245","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
MetallPub Date : 1907-12-31DOI: 10.1515/9783112510766-008
{"title":"7.Metallarbeiten aus dem Orient und Osteuropa","authors":"","doi":"10.1515/9783112510766-008","DOIUrl":"https://doi.org/10.1515/9783112510766-008","url":null,"abstract":"","PeriodicalId":35782,"journal":{"name":"Metall","volume":"4 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"1907-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79693286","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}