There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

High temperature solid-lubricating materials: A review

Sputter deposition of transition-metal carbide films - A critical review from a chemical perspective

High-entropy ceramics with five or more cations have recently attracted significant attention due to their superior properties for various structural and functional applications. Although the multi-component ceramics have been of interest for several decades, the concept of high-entropy ceramics was defined in 2004 by producing the first high-entropy nitride films. Following the introduction of the entropy stabilization concept, significant efforts were started to increase the entropy, minimize the Gibbs free energy and achieve stable single-phase high-entropy ceramics. High-entropy oxides, nitrides, carbides, borides and hydrides are currently the most popular high-entropy ceramics due to their potential for various applications, while the study of other ceramics, such as silicides, sulfides, fluorides, phosphides, phosphates, oxynitrides, carbonitrides and borocarbonitrides, is also growing fast. In this paper, the progress regarding high-entropy ceramics is reviewed from both experimental and theoretical points of view. Different aspects including the history, principles, compositions, crystal structure, theoretical/empirical design (via density functional theory, molecular dynamics simulation, machine learning, CALPHAD and descriptors), production methods and properties are thoroughly reviewed. The paper specifically attempts to answer how these materials with remarkable structures and properties can be used in future applications.

High-entropy ceramics: Review of principles, production and applications

Boron compounds are widely used in a range of tribological applications such as friction modifiers, antioxidants, antiwear additives, and in many cases as environmentally friendly lubricants. The chemical nature and structure of boron compounds provide multifunctionality. They are used as (1) solid lubricants such as boric acid and hexagonal boron nitride, (2) liquid lubricants such as ionic liquids, (3) lubricant additives such as borate derivatives of various organic and inorganic compounds, and (4) coatings such as cubic boron nitride and different metal borides. Boron is also one of the most favorable elements for coatings and thin films in biotribological and biomedical applications. This review outlines the growing role of boron in lubrication over the past several decades, summarizes the main findings, and identifies future challenges related to boron chemistry.

Boron in tribology: from Borates to ionic liquids

Microstructure, mechanical and tribological characterization of CrN/DLC/Cr-DLC multilayer coating with improved adhesive wear resistance

the National Natural Science Foundation of China (50905177);the Chinese Academy of Sciences (KJZD-EW-M01)

A Near‐Frictionless and Extremely Elastic Hydrogenated Amorphous Carbon Film with Self‐Assembled Dual Nanostructure

Doped graphite-like coating (GLC) has aroused great interest as one of the most promising protective materials in marine applications. However, there is a lack of systematic research on the tribocorrosion and antifouling performance of doped GLC coatings in harsh marine environments. Herein, a multifunctional (Cr, Cu)-GLC coating with combined antifouling and tribocorrosion properties was prepared via a magnetron sputtering method. The experimental results indicate that the resultant coatings changed from a dense structure to a loose columnar structure with the increment of Cr and Cu doping amount. At the same time, the hardness of the coating gradually decreases, but the contact angle between coating and seawater gradually increases. The algae adhesion test reveal that the algae density on the surface of the (Cr, Cu)-GLC coating decreases from about 565 to 70/mm2 as the amount of doping increased. However, on the contrary, the friction coefficient of the coating under OCP condition increases from 0.06 to...

Junying Hao

Papers

Microstructure, mechanical and tribological characterization of CrN/DLC/Cr-DLC multilayer coating with improved adhesive wear resistance

A Near‐Frictionless and Extremely Elastic Hydrogenated Amorphous Carbon Film with Self‐Assembled Dual Nanostructure

Tailoring the Tribocorrosion and Antifouling Performance of (Cr, Cu)-GLC Coatings for Marine Application.

Improved toughness of layered architecture TiAlN/CrN coatings for titanium high speed cutting

High-temperature tribological behavior of a nickel alloy matrix solid-lubricating composite under vacuum