Fabrication of a durable and strong nanopatterned mold insert using metal sheet and plate is important for molding of thermoplastic materials. Conventionally, the nickel stamper replicating a master pattern by electroforming process has been used for injection molding of nanotextured products such as Blu-ray media. However, a more facile and cheaper mold fabrication process is highly required for manufacturing of functional products based on nanostructured surface. In this study, zirconia nanoparticles were blended with UV curing polymer to fabricate a polymer nanocompositebased nanopattern mold. Compared to the cured pure Ormostamp, the modulus of elasticity of the nanocomposite filled with approximately 54 vol% of zirconia nanoparticles increased by 160 times. Additionally, the modulus of elasticity reached 197 ㎬ by thermal decomposition of the UV-Cured polymer and post-annealing at 800°C of the nanoparticle layer. The nanopatterns were formed on stainless steel sheet and block, and applied to hot embossing of the PMMA films and injection molding of the COC materials, respectively. No deterioration of the mold occurred during the hot embossing 30 times and the injection molding 600 shots. Nanoparticle-enhanced UV curing nanocomposites or post-heat treatment methods are cost-efficient and easy, because many molds can be manufactured from one master pattern.

The objective of this study was to investigate wear characteristics of Fe-TiB₂ composites prepared by pressureless sintering (PLS) and spark plasma sintering (SPS) using nanocomposite mixtures. Prior to wear test, micro-structures and mechanical properties of specimens were examined. Wear characteristics of these specimens slid against SiC were assessed using ball-on-disk tribo-tester. Results showed that PLS specimen had significantly large TiB₂ particles in the Fe matrix than SPS specimen. The relatively large TiB₂ particles in PLS specimen might be due to grain growth and coarsening during sintering process. Hardness of SPS specimen was substantially larger than that of PLS specimen. Furthermore, SPS specimen exhibited significantly larger wear resistance than PLS specimen. These differences in hardness and wear resistance between specimens might be associated with differences in their micro-structures. Results of this study provide better understanding of wear characteristics of Fe-TiB₂ composites.