Search Results for erosion resistance

Thermal barrier coatings (TBCs) with segmented or cracked microstructures exhibit enhanced thermal cyclic behavior and erosion resistance, along with improved application economics, over conventional TBCs.

An investigation into the chemistry and type of tungsten carbide powder used for drill bits has yielded a material with improved transverse rupture strength and interesting microstructural response to thermal cycling.

This article discusses some of the newer thermal barrier coating materials being considered for use in gasified coal-based turbines and how they compare with conventional materials in terms of bond coat oxidation and topcoat damage due to particle erosion and molten ash deposits.

3D laser microscopy is opening new areas of study for metallic alloys and coatings in power generation applications. This article describes some case studies where laser microscopy has augmented, and in some cases replaced, metallic alloy characterization using optical microscopy or scanning electron microscopy.

Clearance-control coatings play a major role in gas turbine engines by minimizing the air gap between rotating blade tips and engine casings. An improvement of just 125 µm can reduce fuel consumption by 0.5%. This article discusses the potential impact of new materials being considered for blade tip coating systems, including NiCoCrAlY bond coats and matrix layers with Hf, Re, or Si additions for better oxidation and creep resistance, embedded angular CBN particles for enhanced incursion of abradable shroud coatings, and double or Pt aluminide topcoats for extended oxidation protection.

Nanostructured tungsten-tungsten carbide chemical vapor deposition (CVD) coatings provide a practical, technical, and commercially viable alternative to hard chrome plating for aircraft components.

Thermal spray coatings are widely used to keep power plants running at full capacity. An example is the application of HVOF-sprayed CrC-NiCr to protect generating and superheater banks from sulfuric and vanadium gases. Other examples include the use of arc spraying to deposit high Cr content Ni alloy to extend the life of coal-fired boiler tubes and to apply amorphous work hardening coatings to surfaces in the flu gas path that are susceptible to high-temperature corrosion and wear.

Conventional manufacturing from wrought bar stock typically involves extensive machining, creates significant material waste (scrap metal), and requires numerous steps to obtain the final part geometry. As a more efficient alternative, powder metallurgical (PM) processes are now available to cost effectively fabricate both simple and complex shapes with minimal material waste. Combustion driven higher pressure powder compaction (CDC) for near-net or net shape manufacturing was recently developed. It offers a unique way of forming near-net or net shape high-density powder metal components both cost effectively and at relatively higher compaction pressures than other PM processes.

New thermal spray methods optimized for the production of functional coatings are bridging the gap between traditional thermal spraying and thin-film deposition technologies. Two such methods, one known alternately as very low pressure plasma spraying (VLPPS) or plasma spray-physical vapor deposition (PS-PVD) and one called thin-film thermal spray chemical vapor deposition (CVD), are briefly reviewed here.

Profile of William E. Frazier, the 2016-2017 President of ASM International.

Direct write technology is an innovative and economical materials deposition process that integrates conductive traces, antennas, circuits, and sensors onto components or embeds them within structures. The process has been in development since 2002 for use in aerospace, military, and energy markets. This article describes its use to print thermocouple sensors, heat flux sensors, heaters, conductors, and antenna patterns.

Capable of stopping 50-caliber, armor-piercing rounds, ALON and Spinel are hard and durable transparent polycrystalline materials manufactured using powder based processes. This article describes their unique combination of mechanical, optical, and chemical properties, and reports on recent advances in manufacturing to enable their use for critical defense, industrial, and consumer applications.

Titanium boron composite coatings with superior wear performance were selected for use in materials experiments on the International Space Station. The titanium-boron nitride composite coatings were prepared using an atmospheric plasma spray technique from engineered composite powders. The coatings were subjected to extensive characterization and tribological studies. The results show tremendous improvement in the wear performance.

Boronizing 3D-printed Inconel 718 for improved wear resistance produces results similar to those obtained for wrought 718.

This article presents an overview of the use of thermal spray technology at The Boeing Co., dating back to 1968 when the first thermal spray specification, "Plasma Flame Spray Coating," was released. It also discusses anticipated needs based on industry trends.

Advanced materials engineering is being used to solve component life cycle improvement challenges in extremely harsh working conditions. This article discusses examples from various industries where new materials and surface modifications are used to extend the useful life of engineering components and equipment.

This article describes work being done at the University of Limoges to develop thermal spray coatings for use in new nuclear power plant designs.

Thermal spray plays an important but latent role in many energy generation applications. Strong R&D commitment is required to further expand its technological envelope. This article addresses future directions in the use of thermal spray coating technologies in the energy sector.

Using thermal spray to coat the interiors of pipes and tubes used in heavy duty applications enhances mechanical properties and extends component lifetimes. This article describes results from a trials to optimize coating properties produced with new hardware designed to coat pipe interiors with diameters down to less than 5 inches, which has traditionally been a challenge for the production of high quality coatings.

Through a series of case studies, the benefits of micro x-ray fluorescence (XRF) over traditional XRF are demonstrated in the power generation industry for informing weld procedures, identifying root cause, and providing materials or component specifications.