Sample preparation and testing methods for the evaluation of microcrystalline waxes for the seismic protection of art objects

Abstract

Use of microcrystalline waxes for the protection of ceramic art objects from seismic events is an inexpensive and relatively popular technique. Unfortunately, because of the high porosity of some ceramics and the fragility of their glazes and paints, the surface of many art objects may be vulnerable to damage from the microcrystalline wax. Thus, a conservative application approach is needed – applying only as much as is actually required for predicted levels of ground movement. Determining this quantity and verifying the best application technique (e.g. hot versus cold) has yet to be established. This paper presents the development of testing techniques to optimize the application of microcrystalline waxes, specifically, the pioneering of tensile and shear sample preparation. These procedures were applied to 70 tensile and 175 shear tests on paraffin wax, beeswax, and 4 microcrystalline waxes. Static testing methods demonstrated the clear superiority of certain products and average performance capabilities of up to 167kN/m2 in tension and 89 kN/m2 in shear under light loading.