PROPERTIES OF MAGNESIUM-PHOSPHATE-BONDED REFRACTORY CASTABLES
George D. Gower, P.E, and Irv W. Gower, P.E
ABSTRACT
Phosphate-bonded products have been used for many years in dental prosthetics and cements, in highway repair, and for refractory applications. While phosphates have been used in the creation of refractory mortars and plastics, they have not been used extensively in refractory castables. A magnesium-phosphate castable has been developed utilizing a closely-graded, sintered mullite aggregate with a magnesium phosphate/magnesium oxide/aluminum oxide binder. A magnesium phosphate castable’s advantageous properties include a fast (yet retardable) set, and strength that increases when the product is fired to mid-range temperatures (approx. 1500° F) and, in general, over time.
For complete text please send an e-mail to info@phosphatebonds.com
-----------------------------------------------------------------------------------------------------------------------------
Phun with REF-BOND BMAP
By George Gower, P.E.
REF-BOND BMAP (BMAP)
BMAP is a buffered mono aluminum phosphate solution. It is designed to be used in the phosphate bonding of refractory plastics. BMAP contains buffers and plasticizers to improve the performance of refractory plastics and imparts superior workability along with extended shelf life.
Abstract:
BMAP is compared to other sources of P2O5in a phosphate bonded plastic. Test mixes were produced using BMAP, a commercially available Mono Aluminum Phosphate Solution and 75%ºPhosphoric acid. A standard test mix was developed and the samples were followed through about 60 days of aging. To compare strength hot MOR’s were conducted at 1500 and 2500 ºf.
For complete text please send an e-mail to info@phosphatebonds.com
-------------------------------------------------------------------------------------------------------------------------------
Phun with Mono Magnesium Phosphate
By George Gower, P.E.
Introduction:
Ref-Bond MP2 (MP2) is a family of products which are used in refractories where a source of dry P2O5 is required. MP2 can be used to form cement with the addition of alkali. Other uses for MP2 include gunning, dry mortars and technical cements. One of the early uses for MMP is in the area of dental investment casting. Cement produced with MP2 bonds readily to itself and other material such as steel. Table 5 shows the chemistries for Ref-Bond MP2 products. RMCI produces this material in large batches which are then homogenized to maintain consistency from lot to lot. MP2 is an excellent source of P2O5 where a liquid phosphate is inconvenient to use.
For complete text please send an e-mail to info@phosphatebonds.com
-----------------------------------------------------------------------------------------------------------------------------