Recent Patents on Materials Science - Volume 5, Issue 1, 2012

Recent Patents on Material Science was launched in 2008. This important patent journal is publishing review and research articles in varied disciplines of Material Science. Methods, design and techniques in materials, biomaterials, biological material, magnetic materials, medical implant materials, nonmaterial's, ceramic, plastics, composites, polymers, coatings, wood, textile, semi-conductors are generally covered. Muralidhar et al. reviewed the advances in technical aspects for the manufacturing of bulk- LRE- Ba2Cu3Oy superconductors (light rare earth elements i.e. Nd, Eu and Sm based YABCO materials) and its application at high temperature up to liquid oxygen boiling point and high magnetic fields in his comprehensive research article. The mechanism of flux pinning control plays an important role to improve the critical current density, and experiments have shown melting of processed materials. The effects of (Nd, Eu, Gd) 123 were associated with standard twin structure. The nanometer sized defects in NEG-123 and flux pinning at higher temperatures in NEG-123 and irreversibility at 77K were also discussed. In US8072711, Wang disclosed magnetoelectronic response of Co/Cu/Co/Fe spin valves annealed thermally at different temperatures ranging from 200°C to 350°C. The magnetic characteristics of nano-structured magnetic materials are considered useful in corrosion testing [1]. Heat capacity measurements were conducted to study the magnetocaloric and magnetic properties of Gd1-xScxNi2 solid solutions at Curie temperature below 76K [2]. The patented methodology for the production of permanent magnet was reported comprising melting boron, cobalt, a metallic alloy component consisting of aluminum, copper, niobium, gallium, vanadium, chromium, zirconium or any combination, 28-35 weight percent of a mixed rare earth material (50 weight percent of praseodymium and 5-50 weight percent of neodymium) and heavy rare-earth material comprising dysprosium or a combination of dysprosium and terbium, and iron [3]. Balaji and co authors [4] reported giant magnetostriction (δ ≤ 10-3) in TbFe, TbFe2, DyFe2 and Terefenol-D magnetic nanoparticles by in-field small angle X-ray scattering (SAXS). Recently, magnetic tri-axial orientation in (Y1-xEr x)2Ba4Cu7O15-y superconductors was proposed to observe changes in the magnetic easy axis at room temperature for different rare earth ions [5]. Sopyan and co-authors discussed the use of metal - doped calcium phosphonate based biomaterials as an alternative human bone implant. This property of bone implant materials is attributing to its varying restorability and high compatibility. Pysicochemical, biological and mechanical characteristics of metal - doped hydroxyapatite for biomedical and clinical applications were also focused by the authors. Recent patents on the preparation and role of monovalent (Li, Na, K, Ag), divalent (Mg, Sr, Zn, Mn, Si, Cu, Co and trivalent (Cr, Fe, Eu, Bi, In, La, Ga, T) metal - doped calcium phosphate calcium phosphate based nanoparticles (CAPNP) were disclosed. These metals serve as a bone implant, a dental implant, bone replacement material or a soft tissue substitute or a dental substitute, bone graft, bone scaffold or as a filler. Sirivisoot and the group presented a method for the measurement of electrochemical properties. The method relates to the enhancement of osteoblast functionality of a medical implant. The method involves change surface characteristics which results in increased functionality of osteoblast next to implant surface. They have also studied methods for manufacturing a medical implant with a biosensor for in vivo use and monitoring conductivity and electrochemical changes with the help of biosensor [6]. In another US20110178525 patent, the biomaterials comprising calcium phosphate, such as hydroxyapatite or a material biphasic calcium phosphates and calcium phosphate cements are disclosed to be used as an implant for filling bone defects, bone tissue regeneration and dental surgery [7]. A porous implant containing a porous portion coated with a calcium phosphate compound forms bisphosphonate layer by chemically reacting with bisphosphonate compound. This layer chemically bound to the calcium phosphate at the surface of the porous portion and form non-chemically bisphosphonate molecules attached inside the pores of the porous portion. The use of mixture of tricalcium phosphate and hydroxyapatite or tricalcium phosphate as coatings in hip and dental implants was also disclosed [8]. Daculsi et al. reported grit blasting process involving biphasic calcium phosphate, a Resorbable Biocompatible Blast Media (RBBM) for the improvement of bone ingrowth on PEEK surface implant. These studies showed high biocompatibility and bone osteoconduction, and enhance stability of the implant [9]. Recently, it is reported that Calcium phosphate / polyurethane composites are used as a substitute graft material for the treatment of bone problems, femoral defects and especially for weight-bearing orthopedic implants. Synthetic studies were also conducted and in vitro cellular response and in vivo bioactivity along with mechanical properties and were also examined for both hydroxyapatite (HA) and β-tricalcium phosphate (TCP) composites [10]. Meola and Toscano focused on ultasonic testing and infrared thermography and some other techniques like imaging for the nondestructive (NDE) evaluation and testing of composites particularly aerospace (space shuttle) and transport parts (race cars) etc. Carbon fiber reinforced polymers (CFRP) preparations methods and detections of defects and damage of composites are also covered. The use of epoxy-based polymeric compositions for the preparation of fiber reinforced polymer material is recently disclosed by Barra amd inventors [11]. Composition claims to be is used in civil, aerospace and motor industries and sporting plants at environmental temperature. The fiber reinforced polymer comprises a polymer matrix and reinforcing fibers (carbon fibers or, glass fiber or Kevlar®) to reveal high resistance. Lorraine et al. disclosed a method and apparatus for spectroscopic investigation of a material using a laser ultrasound system. The method involves measurement of amplitude displacement of a target surface agitated with a generation laser [12]. Thermographic detection of internal passageway blockages based on the temperature response signal was studied in recent patent WO2011156040 [13]. Carbon fiber reinforced polymer (CFRP) composites due to its astonishing mechanical properties in the longitudinal direction are used in aerospace, bio-implant engineering and light-weight automobiles. A technique is reported to improve the transverse mechanical properties of CFRP composites. Addition of magnetic aligned carbon nanotubes resulted in a considerable increase in the transverse stiffness of the CFRP composites [14]. Preparation of multiscale carbon nanotubehybridized carbon fiber has been recently studied by An et al. The characterization of carbon nanotube-hybridized carbon fiber was done by Scanning electron microscopy and transmission electron microscope. Different carbon nanotube-hybridized carbon fiber to reinforce epoxy composite was proposed and compared with one reinforced by the original carbon fiber [15]. Computed tomography (CT) was performed to investigate the fatigue mechanisms of Glass Fibre Reinforced Polymer (GFRP) used in wind turbine blades. The role of void and three dimensional damage properties in fatigue was also characterized by Lambert et al. [16]. Similarly, the lock-in infrared thermography technique was used for establishing the fatigue limits and compared with existing fatigue limits of 2A12 aluminum alloy [17]. Thermal samarium zirconate barrier coatings are studied attributing to low intrinsic thermal conductivities and stability above 1200°C as compared to yttria-stabilized zirconia [18]. Nourani et al. reviewed the current microstructural trends of 4130 steel alloys in the production of high pressure gas containers and CNG gas cylinders through hot compression processes with related patents. Temperature and strain rate are important process parameters for identifying microstructure of alloys. The dynamic crystallization, grain size and mechanical aspects are also discussed in this article. US20110108164 patent relates to exclusive thermal methods and devices for the mechanical processing of martensitic stainless steel and products and applications. Hot compression testing of forged materials is studied at varying temperatures, strain rates and total strains conditions [19]. Improved production method for titanium wire with modified microstructures properties such as high TiB content and small reinforcement grain size is also discussed [20]. Sajadifar et al. reported the effectiveness of hot compression tests which are performed at 900°C - 1100°C and strain rate of 0.001 - 0.1 s-1 to investigate hot deformation behavior and flow stress model of 4130 steel [21]. The solid-state sintering process for the synthesis of tricalcium phosphate (TCP) and zinc doped monophasic/biphasic α/β-TCP dense biomaterials is recently reported by Carbajal et al. The processing is performed by using different ZnO contents and controlled phase proportions and microstructure on the final material. ZnO doped tricalcium phosphate based biomaterials are comparable to natural bone composition and promote bone growth and mineralization process [22]. The Editor-in-Chief is most grateful to the authors of this first journal issue for 2012 for their scientific contributions of review and research articles and acknowledges the efficient cooperation of our reviewers for their valuable comments and recommendations for improving the overall quality of these articles. We look forward to receiving more articles and proposals for thematic issues to Recent Patents on Materials Science. REFERENCES [1] Wang, J.-Q. System and method for the fabrication, characterization and use of magnetic corrosion and chemical sensors. US8072711 (2011). [2] Cwik J, Palewski T, Nenkov K, Warchulska J, Klamut J. Magnetic and magnetocaloric properties of Gd1-xSc xNi2 solid solutions. J Magn Magn Mater 2012; 324(5): 677-82. [3] Dong, S., Haran, K.S., Yang, C., Liu, X., Guo, S., Chen, B. Method of fabrication of mixed rare-earth permanent magnet. US20110236246 (2011). [4] Balaji G, Narayanan RA, Weber A, Mohammad F, Kumar CSSR. Giant magnetostriction in magnetite nanoparticles. Mat Sci Eng B-Solid 2012; 177(1): 14-8. [5] Horii S, Okuhira S, Yamaki M, Haruta M, Maeda T, Shimoyama J. Magnetic tri-axial orientation in (Y1-xEr x) 2Ba4Cu7O15-y superconductors. Physica C 2011; 471(21-22): 867-71. [6] Sirivisoot, S., Yao, C., Xiao, X., Sheldon, B., Webster, T. Method to enhance osteoblast functionality and measure electrochemical properties for a medical implant. US20110301716 (2011). [7] Balaguer, T., Rochet, N., Carle, G. Biomaterials containing calcium phosphate. US20110178525 (2011). [8] Bobyn, J.D., Tanzar, M. Implant improving local bone formation. US8071574 (2011). [9] Daculsi G, Goyenvalle E, Aguado E. Improvement of bone ingrowth on PEEK surface implant. Key Eng Mat 2012; 493-494: 795-9. [10] Yoshii T, Dumas JE, Okawa A, Spengler DM, Guelcher SA. Synthesis, characterization of calcium phosphates/polyurethane composites for weightbearing implants. J Biomed Mater Res B 2012; 100B (1): 32-40. [11] Barra, G., Lavorgna, M., Mensitieri, G., Piscitelli, F. Fiber reinforced polymers, epoxy-based polymeric compositions and use thereof. US20110112222 (2011). [12] Lorraine, P.W., Drake, Jr. T.E., Deaton, Jr. J.B., Dubois, M., Filkins, R. Method and apparatus for spectroscopic characterization of samples using a laser-ultrasound system. US8054470 (2011). [13] Shepard, S.M., Lhota, J.R., Ahmed, T., Chaudhry, B.B. Thermographic detection of internal passageway blockages. WO2011156040 (2011). [14] Aldajah S, Haik Y. Transverse strength enhancement of carbon fiber reinforced polymer composites by means of magnetically aligned carbon nanotubes. Mater Des 2012; 34: 379-83. [15] An F, Lu C, Li Y, Guo J, Lu X, Lu H, et al. Preparation and characterization of carbon nanotube-hybridized carbon fiber to reinforce epoxy composite. Mater Des 2012; 33(1): 197-202. [16] Lambert J, Chambers AR, Sinclair I, Spearing SM. 3D damage characterization and the role of voids in the fatigue of wind turbine blade materials. Compos Sci Technol Artilce in press. [17] Li XD, Zhang H, Wu DL, Liu X, Liu JY. Adopting lock-in infrared thermography technique for rapid determination of fatigue limit of aluminum alloy riveted component and affection to determined result caused by initial stress. Int J Fatigue 2012; 36(1): 18-23. [18] Zhao H, Begley MR, Heuer A, Sharghi-Moshtaghin R, Wadley HNG. Reaction, transformation and delamination of samarium zirconate thermal barrier coatings. Surf Coat Technol 2011; 205(19): 4355-65. [19] Jain, S.K., Hammond, S.N. Thermal mechanical processing of stainless steel. US20110108164 (2011). [20] Hanusiak, W.M., Fields, J.L., Hammond, V.H., Grabow, R.L. Method for manufacturing titanium alloy wire with enhanced properties. EP1784269 (2011). [21] Sajadifar SV, Ketabchi M, Nourani M. Modeling of mechanical characteristics in hot deformation of 4130 steel. Steel Res INT 2011; 82(8): 934-9. [22] Carbajal L, Caballero A, Sainz MA. Design and processing of ZnO doped tricalcium phosphate based materials: Influence of α/β polymorph phase assemblage on microstructural evolution. J Eur Ceram Soc 2012; 32(3): 569-77.

In this patent review the progress in technology and prospects of bulk ternary LRE-Ba2Cu3Oy “LRE-123” (LRE=light rare earth, Nd, Eu, Sm, Gd) superconductors are presented. Number of experiments has proven that ternary LRE-123 melt processed materials exhibit excellent properties appropriate for development of bulk high-field high-Tc superconducting magnets. The key prerequisite for success in controlling flux pinning in these materials at high magnetic fields is creation of pinning defects with distinct superconducting properties compared to the superconducting matrix. In (Nd,Eu,Gd)-123 critical current density achieved the level of 105A/cm2 at 65K in self-field and 5T and the irreversibility field Birr (the field limit above which the superconductor looses its ability to carry electric current) approached 15T at 77K. The high critical current density at low and intermediate fields, persisting up to the boiling point of liquid oxygen (90.2K), close to Tc, is mainly due to size reduction of normal-conducting or insulating pinning defects up to nanoscale level. Such pinning sites are e.g. nanoscale secondary phase particles, Zr-, Nb-, Mo-, or Ti- oxides. In some particular (Nd,Eu,Gd)-123 compositions Birr increased twice due to a nanoscale planar substructure correlated with the regular twin structure.

For many years calcium phosphate based materials have been used to create bone substitutes as alternatives to human transplant. Most calcium phosphate biomaterials are characterized by high biocompatibility and excellent ability to undergo varying degrees of resorbability. Numerous investigations have been made to study calcium phosphate ceramic materials as bone substitutes. This patent review however, focuses on metal-doped calcium phosphates produced by various methods for clinical applications. A variety of synthesis methods have been employed to produce metal-doped calcium phosphates and different methods may produce different final products and characteristics in terms of crystallinity, morphology and stoichiometry. There are many metal ions such as magnesium (Mg), strontium (Sr), manganese (Mn), iron (Fe), zinc (Zn) and silver (Ag) that have been doped successfully into calcium phosphates to enhance their mechanical and biological properties. These biomaterials can be served as scaffold for bone regeneration with adequate mechanical properties to restore bone defects and facilitate healing process. The significant improvement in certain metal-doped calcium phosphates in terms of physico-chemical, biological and mechanical properties has shown the relevance in the development of metal-doped HA for biomedical applications. This paper provides a review of doping of the most common metals into calcium phosphate phase in order to optimize its performance as bone substitute materials. Some recent patents related to metal doped calcium phosphate ceramics are also reviewed.

The increasing use of composites in the transport industry and specifically in the aerospace field calls for nondestructive evaluation techniques for quality control during manufacturing and in service. Therefore, the availability of techniques which are effective to assess a material is free of slag inclusions, delamination and porosity is a crucial point. Of course, no technique is exhaustive alone; some are more effective for detection of surface discontinuities, others for outlining of buried shallow defects and others for detection of deeper anomalies. Then, an integration of two, or more, techniques may be the optimal solution especially for nondestructive evaluation of aerospace parts. The attention of this review is focused on two techniques: ultrasonic testing, which is commonly used, and infrared thermography, which was recently recognized amongst standards, for nondestructive testing and evaluation of composite materials in the aeronautical industry. For each of the two techniques, historical steps are traced with particular attention to the patents produced. In particular, the advantages coming from an integration of infrared thermography with ultrasonics and some other techniques are also discussed.

Extraction of Cu2+ , Co2+ and Ni2+ ions from aqueous solutions of bromide ion using 1-phenyl-3-methyl-4- trichloroacetylpyrazolone-5 (HTcP) in benzene and hexane organic medium has been studied. From the results, extraction of Co2+ and Ni2+ ions was masked by anionic complexes of the bromide ions throughout the pH range of 0 - 6. Cu2+ ions were quantitatively extracted from aqueous solutions of bromide ions, thereby presenting a technique for the efficient separation of Cu2+ ions from Co2+ and Ni2+ ions. Increase in bromide ion concentration from 0.05 to 0.3M had a salting out effect on the extraction of Cu2+ ions from 97.44% to 98.79% in benzene/HTcP medium and 97.13% to 98.33% in hexane/ HTcP. On application of statistical treatment using slope analysis, the values of pH1/2, log Kex and log Kd have been calculated and presented. Hence, the complex formed is Cu(TcP)2. Generally, extraction of Cu2+ ions was found to be more efficient in hexane/HTcP at relatively lower pH value in comparison to extraction into benzene/HTcP, while optimal percentage yield was slightly higher in benzene/HTcP than hexane/HTcP solution. This can be attributed to the lower dielectric constants of hexane (2.02) and lower dipole moment in comparison to that of benzene (2.28). Finally, molecular modeling shows that the stable structure of the ligand derivative (HTcP) was quite different in orientation from the parent ligand (1-phenyl-3-methyl-4-acetylpyrazolone-5 HPMAP) and has been attributed to the bulky nature of the trichloro unit. This has been discussed in line with relevant patents.

This article first gives a brief patent review of recent trends of steel alloys used in the manufacturing of highpressure gas containers. 4130 steel is among such alloys and has been extensively used in natural gas cylinders that are manufactured through the hot deformation processes. Due to the importance of process parameters such as temperature and strain rate on the ensuing microstructure, primarily grain size, and mechanical properties of the cylinder, the dynamic recrystallization characteristics of 4130 steel are investigated in the second part of this article. Hot compression tests on 4130 steel specimens have been performed at a temperature range of 900-1100°C, strain rate range of 0.001-0.1s-¹ and the strain of 0.9. The resulting flow stress curves show the occurrence of dynamic recrystallization with single or multiple peaks, before reaching the steady state flow at different temperatures and strain rates. The effect of various processing parameters on the microstructure of the alloy is identified by microstructural examination focusing on revealing primary austenite grains using special etchant solutions. It is found that the average grains size of the deformed 4130 steel increases with an increase of the forming temperature and a decrease in the strain rate. The grain size is decreased with an increase of the steady state stress.

The patents annotated in this section have been selected from various patent databases. These recent patents are relevant to the articles published in this journal issue, categorized by materials, biomaterials, biological materials, magnetic materials, medical implant materials, nanomaterials, ceramics, plastics, polymers, semi-conductors, coatings, composites, paper, wood, textile, methods, design and techniques.