THE COMPOSITION OF THE TRICALCIUM ALUMINATE AND FERRITE PHASES IN PORTLAND CEMENT DETERMINED BY THE USE OF AN ELECTRON-PROBE MICROANALYSER

ANALYSIS OF THE TRICALCIUM ALUMINATE AND CALCIUM ALUMINO- FERRITE PHASES IS DESCRIBED. IT WAS DIFFICULT TO OBTAIN RELIABLE AND ACCURATE ANALYSES OF THESE IN PORTLAND CEMENT CLINKERS AND RESULTS WERE CONFIRMED BY THE INVESTIGATION OF LABORATORY PREPARATIONS WHERE THE TRICALCIUM ALUMINATE AND CALCIUM ALUMINO-FERRITE PHASES WERE PREDOMINANT. THE TRICALCIUM ALUMINATE PHASE WAS FOUND TO BE APPROXIMATELY: (CALCIUM 2.78 SODIUM 0.16 POTASSIUM 0.02) (ALUMINUM 1.75 IRON 0.16 MAGNESIUM 0.07 SILICON 0.10)06. THE CALCIUM ALUMINO-FERRITE PHASE IN A NORMAL PORTLAND CEMENT CLINKER WAS FOUND TO BE: CALCIUM 5.97(ALUMINUM 3.23 IRON 2.13 SILICON 0.14 MAGNESIUM 0.15 TITANIUM 0.23 MANGANESE 0.09)015 AND THAT IN A SULPHATE-RESISTING CEMENT CLINKER TO BE: CALCIUM 6.16(ALUMINUM 2.24 IRON 3.22 SILICON 0.14 MAGNESIUM 0.07 TITANIUM 0.12 MANGANESE 0.03)015. THE PROPERTIES OF A PORTLAND CEMENT ARE LARGELY GOVERNED BY THE RELATIVE AMOUNTS OF THE FOUR MAJOR PHASES PRESENT. THE NORMAL 'BOGUE' METHOD OF COMPOUND CALCULATION FROM THE CHEMICAL ANALYSIS ASSUMES THAT NO SOLID SOLUTION OCCURS IN THESE PHASES AND THAT THE CEMENT CLINKER IS AT EQUILIBRIUM. THIS METHOD OF COMPOUND CALCULATION IS COMPARED, FOR A SERIES OF CEMENT CLINKERS, WITH A CALCULATION WHERE SOLID SOLUTION IS TAKEN INTO ACCOUNT, WITH A CALCULATON WHERE THE FERRITE COMPOSITION AS GIVEN BY X-RAY DIFFRACTION IS USED, AND ALSO WITH THE DIRECT DETERMINATION OF THE PHASES BY X-RAY DIFFRACTION AND OPTICAL MICROSCOPY. IT SEEMS LIKELY THAT THE NORMAL METHOD OF COMPOUND CALCULATION UNDERESTIMATES THE TRICALCIUM ALUMINATE CONTENT OF SULPHATE-RESISTING CEMENT CLINKERS. /RRL(A)/

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/00249831
• Supplemental Notes:
  • Vol 21, No 66, PP 3-14, 5 FIG, 10 TAB, 16 REF
• Authors:
  • Fletcher, K E
• Publication Date: 1969-3

Media Info

• Serial:
  • MAGAZINE OF CONCRETE RESEARCH
  • Publisher: Thomas Telford Limited
  • ISSN: 0024-9831

Subject/Index Terms

• TRT Terms: Aluminates; Calcium compounds; Chemical analysis; Clinkers; Diffraction; Electrons; Ferrites; Microanalysis; Microscopes; Portland cement; Probes (Measuring devices); Sulfate resisting cement; X rays
• Uncontrolled Terms: Optical microscopes; X-ray diffraction
• Old TRIS Terms: Electron probes
• Subject Areas: Highways; Materials;

Filing Info

• Accession Number: 00212989
• Record Type: Publication
• Source Agency: Road Research Laboratory /UK
• Files: TRIS
• Created Date: Apr 25 1971 12:00AM