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

Effect of nano-SiO2 on the performance of starch/polyvinyl alcohol blend films

Thermomechanical processing of advanced high strength steels

The structure and properties of a starch-based biodegradable film

Thermohydrogen processing is a technique in which hydrogen is used as a temporary alloying element in titanium alloys to control the microstructure and improve the final mechanical properties. Thermohydrogen processing can also be used to enhance the processability/fabricability of titanium products including sintering, compaction, machining, and hot working (forging, rolling, superplastic forming, etc.). In the case of near net shapes, such as castings and powder metallurgy products, thermohydrogen processing is the only method available for significant microstructural modifications and consequent enhancement in mechanical properties. This paper reviews the status of the methods and applications of thermohydrogen processing to titanium alloys. Principles of thermohydrogen processing, based on the hydrogen induced alterations of the phase compositions and the kinetics of phase reactions in hydrogenated titanium alloys, are overviewed. Stable and metastable phase diagrams of several titanium alloys...

Hydrogen as a temporary alloying element in titanium alloys: thermohydrogen processing

In modern industry, the developing tendency and prospect for productions of the oil and gas pipeline steels is to further improve the strength and toughness by advanced manufacture process of the thermo-mechanical control process (TMCP) to refine microstructure. In this work, the hot deformation behavior as well as its effect on the phase transformation of the clean acicular ferrite pipeline steel with simple chemical composition has been investigated. According to the result, the optimum TMCP parameters were designed. Furthermore, the rolling test was carried out on the experimental rolling mill. The results show that, the high strength and excellent toughness of the clean acicular ferrite pipeline steel can be obtained by controlling the TMCP parameters of the production process appropriately. (c) 2006 Elsevier B.V. All rights reserved.

Challenge of mechanical properties of an acicular ferrite pipeline steel

A study on the dual-phase treatment of weathering steel 09CuPCrNi

Effects of Mo, Cr and Nb on microstructure and mechanical properties of heat affected zone for Nb-bearing X80 pipeline steels

Nb is often considered to be a powerful alloying element for controlling the recrystallization process in microalloyed high strength steels. However, Nb can be presented either as solute in solution, where it is thought to exhibit a strong solute drag effect, or as NbC precipitates, which are thought to be effective at pinning grain boundaries. Therefore, it is very important to quantitatively measure Nb in solution or in NbC precipitates. A quantitative analysis method of Nb in solution and in precipitates was proposed. The test procedure involved chemical dissolution, filtration and inductively coupled plasma atomic emission spectroscopic (ICP-AES) analysis. The amount of Nb in solution in Nb-microallyed steels under different treatment conditions was evaluated. The results show that the niobium and carbon contents in steels have a great effect on niobium dissolution kinetics. The solute Nb is more effective to retard dynamic recrystallization, while the NbC precipitates are more effective to inhibit static recrystallization. The results may help to comprehend effect of Nb in steels, and provide some guides in the design of new high strength Nb-bearing steels.

Bo Liao

Papers

Challenge of mechanical properties of an acicular ferrite pipeline steel

A study on the dual-phase treatment of weathering steel 09CuPCrNi

Effects of Mo, Cr and Nb on microstructure and mechanical properties of heat affected zone for Nb-bearing X80 pipeline steels

Effect of Nb Solute and NbC Precipitates on Dynamic or Static Recrystallization in Nb Steels

Effects of rare earth oxide on hardfacing metal microstructure of medium carbon steel and its refinement mechanism