Msterials and Methods
A number of chemical reagents and compounds synthesized in the laboratory were used in this study. A list of these is as follows: CaF 2 -Fisher Reagent Grade Ca3(PO~) 2 -Baker Reagent Grade CaHPO4.2H20 -Baker Reagent Grade Ca(H2PO~)2.H20 -Merck Reagent Grade Ca2P208 -Pyrolysis of CaHPO 4 at 300 Β° C CaH2P207 -Reaction of Ca2P207 with H4P207 (frc~ P205 + HBPO4) Ca2H2P4013 -Pyrolysis of Ca(H2PO~)2.H20 at 300 Β° C for 2 hours NaF -Neutralization of NaOH with HF Ns2SiF 5 -Reaction of HF, Si02, and Na2CO 3 in an adaptation of Balz' method for HBF 4 synthesis (18) Na~lF 6 -Reaction of HF with aqueous Na~lO B NasFeF 6 -Reaction of Na2CO B with a solution of Fe203 in HF Cuspidine -Pyrolysis of stoichiometric quantities of CeO, CaF2, and SiO 2 at 1B15 Β° C
The cements studied were laboratory grinds, using Type I clinker.
The grinds were performed in a jar mill, using s mill load of 1500 g and a ball charge/mill load weight ratio of 6.5. The weight distribution of the ball charge was 36 percent 1.35 cm (17/B2"); 38 percent 1.6B cm (41/6~"); and 26 percent 2.30 cm (29/32") diameter balls. The entire contents of the mill was removed and the sample blended thoroughly prior to each Blaine Surface Area determination.
The chemical analysis of the clinker, the gypsums, and resulting cements typical of those studied sre given in Table I.
The setting time determinations were made according to ASTM standard method of test C-191 in mortar and procedure C-403 in concrete.
The compressive strength results reported here were obtained uslng ASTM procedure C-I09 for mortar and procedure C-192 for concrete.