Recent Patents on Materials Science - Volume 9, Issue 1, 2016

Metallic glasses (MGs) are metallic materials without long-range ordering structures, which endows them with unique properties such as ultrahigh strength and hardness, high wear and corrosion resistances. MGs can be plastically thermoformed like plastics because their viscosity drops with the increase of temperature in their supercooled liquid region (SLR), which is a temperature interval localized between glass transition temperature Tg and crystallization temperature Tx. MGs display good plasticity in the case of high temperature combined with low strain rate. In contrast, when the temperature is under the glass transition temperature (Tg), the deformation is localized into shear bands and fracture occurs immediately after the initiation of shear bands. The material shows an asymmetry between tension and compression. Shear-banding is a plastic-deformation mode in all materials. Particularly, shear-banding is a form of plastic instability that localizes large shear strains in a relatively thin band when a material is deformed. This shear banding behavior of bulk metallic glasses (BMGs) is usually a weakness for these materials but sometimes may be transformed in an advantage by using good engineering solutions. A well known engineering application is the kinetic energy penetrator (KEP), when is used the effect of “self-sharpening” penetration. Shear bands are of crucial importance for deformation behavior of (MGs). Controlling the shear-banding is quite equivalent with the controlling of plasticity and failure at room temperature. This work provides an up-to-date overview on the fundamentals of shear-banding in (MGs) and also of the progress achieved very recently on this subject.

A brief review is presented for patents in the technical domain of numerical analysis on mechanical behavior of formations of unconventional oil and gas. Three technologies of threedimensional (3D) numerical modeling with Abaqus for geomechanics problems existing in petroleum engineering have been critically reviewed. Case 1 is the 3D numerical calculation of mud-weight windows (MWWs). In this work, an integrated 3D method is used, which combines a one-dimensional (1D) analytical tool with the 3D Abaqus finite element (FE) tool. Case 2 is a 3D method for the optimized design of a stage interval of multi-stage hydraulic fracturing, as well as the optimized design of well spacing for horizontal wells of unconventional oil and gas resources. The so-called “real 3D” means that not only the fracture propagation in the vertical and transverse directions, but also the fracture propagation in the lateral direction, will be calculated. This makes the analysis of fracture propagation a full 3D analysis. Continuum damage mechanics (CDM) is used to investigate the development of crack clouds instead of a single crack. Case 3 provides a numerical investigation into sanding prediction for both openhole and cased hole completion forms. Dual-stress-concentration and interpretation on the total amount of plastic strain are analyzed for sanding prediction with the cased hole completion form. These three cases present technology that was disclosed in recently filed patent applications. A discussion of perspective on further development of techniques under this topic is presented at the end of the paper.

In this short statistical report, we compile and analyze statistics on past and current scientific and technological research on photosensitive glass (PG) as well as glass-ceramics (GC). Their developments have traced remarkable histories since their first commercial discoveries in the 1940s and 1950s, both the work of Don Stookey. These products and processes have transformed modern life and are two of the most widely reported methods for special glass manufacturing. They provide security, are of high quality mass production. The U.S., Japan and China have been leaders in PG glass development, the second place going to China in terms of GC research communities. We have observed very significant progress in recent decades with an exponential growth in the number of scientific publications and patents for PGs and GCs due to new publications, author keywords, affiliations and primary characterization techniques. More than 6,497 patents were filed globally prior to 2015 with the terms “photosensitive and glass” and 9,738 with the terms “glass and ceramics” within the title or abstract according to the European Patent Office. These numbers have continued to grow along with worldwide PG and GC-related sales. Based on the Scopus database, for the same period 1,405 PG documents and 30,819 GC-related (primarily manuscripts) were published with the same terms in the title, abstract or keywords list. From this statistical analysis, both PG and GC will continue to be fascinating materials for further research, development and uses in the near future.

This work presents the manufacture and potential application of the ZnO materials with various cation dopings in recent literature and patent and then focus on the deposition and Nd doping effect of ZnO nanoparticles. The influence of Nd-doping in the range of 0-0.79 at % on microstructural and optical properties of ZnO nanoparticles were studied. X-ray diffraction measurement revealed the formation of single-phase ZnO nanocrystallite with a nanoscale particle size in the range of ~36.8-39.5nm. With increasing Nd content, UV-visible light absorbance first decreased and then increased, whereas band gap first widened and then narrowed. The absorbance and band gap show optimal values as Nd content is 0.39 at %. The nanoparticles showed strong visible emission varied with Nd doping due to variation of average particle size. The Nd doping also introduced a new emission center and weakened the visible defect emissions.

Wound infections arising from bacterial contamination and colonisation are of substantial burden to healthcare. Currently, bandages are used to merely provide wounds with physical barriers to bacteria, however they quickly become saturated and ineffective. Silver containing wound dressings have gained commercial and scientific attention as a potential solution to the problem of wound infections. In this work, we compare the antibacterial efficacy of recently patented silver nanoparticle loaded plasma polymer film technology and a commercially available GranuFoam Silver® silver-coated wound dressings. The silver nanoparticle loaded foams contained lower amount of elemental silver than the commercially available wound dressings but both silver-loaded foams had comparable antibacterial capacity. Furthermore, the silver nanoparticle loaded foams had greater hydrophilicity which may be beneficial in applications. Collectively, the results demonstrate that the nanoparticle loaded plasma polymer coating can be used on medical devices such as wound dressings with similar efficacy to existing products.

In this paper, automotive bumper with inner parting structure of injection molding process analysis and mould design was presented. A CAE finite model of bumper was developed by Moldflow simulation software. The effects of processing parameters such as filling time, volume and pressure conversion, injection time, weld lines, air traps, pressure distribution of the end filling, temperature of flow front and volumetric shrinkage at ejection on practical production of the automobile bumper were studied. The paper reviews various patents of injection mould for automobile bumper in the recent years, such as bumper materials, structure and bumper extension. The mould structure design was presented in detail, such as cool system, mould core pulling system, mould ejection system, and opening mould control system. With this kind of design and analysis, quality of part can be promoted maximally and molding period is reduced more. Mould cost on design, manufacture and maintenance can be reduced. The results proved that CAE technology for bumper molding and injection mould design has a strong guiding role.