Comparing Simulation With Gray Iron Casting Trials Using PUCB
Disc-Shaped Sand Specimens (19-207)
Optimizing Gassing and Purging for PUCB
Cold Box Processes
Considerable heat-induced thermo-mechanical reactions occurred in the PUCB samples, as is evident from the surface cracks found on tested specimens and percent change in mass value (Table 2).
Thermo-Mechanical Properties of PUCB Samples PUCB Results of Thermal Distortion Testing Observation Sample at 3.25N for 90 seconds During Elevated Temperature Testing % [D.sub.E] [D.sub.P] [T.sub.D] [D.sub.R] % Binder Longitudi longitudin Total Radial Change nal (mm) al (mm) longitudinal distribution in mass distribution (mm) (mm) 0.9 0.069 0-113 0.182 0.22 8.7 1.4 0.051 0.107 0.158 0.234 1.5 PUCB Sample % Cracks and Binder Fractures 0.9 Faint 1.4 Large Research for the Next Generation Thermal Distortion Tester was supported by the AFS 4F committee.
* The elevated temperature and pressure promoted distortion on the PUCB
This explains the minimal shrinkage from the acrylic epoxy binder that contains lower solvent levels than PUCB binders.
The standard PUCB binder tested used a moderate to low volatility solvent, which may have slowed the shrinkage under the different conditions.
The strength of the PUCB binder increased with time at the 572F and 752F (400C) temperatures while experiencing degradation at all other temperatures.
PUCB systems lose strength and stiffness quickly with moderate to high increases in temperature.
In the HSR samples, the expansion at all PUCB
bonded levels was lower than un-bonded expansion, although PUCB
had less of an effect than on the HSSA samples.
also highlighted its recently expanded range of high-productivity and environmentally friendly core binders to include a new generation of PUCB
Those familiar with phenolic urethane coldbox (PUCB
) binders are well aware of the sheer number of variables that need to be understood and manipulated to achieve the desired property and performance requirements of a good core and a good casting.