This division works on the performance issues and the related mechanisms of materials used in energy systems, including energy production, oil and gas transmission & storage，and those for hydrogen energy. Driven by industry needs, research projects are initiated and conducted  in collaboration with other groups in the centre, other USTB institutes and other research organizations.  Led by a senior professor with over 30 years of research experience, this group works on a range of relevant alloys and coatings that include stainless steels; high strength steels, heat-resistant steels, aluminium alloys, anticorrosive coatings, and composites. This multidisciplinary division values team-work and partnership with clients in delivering research results. Ph. D and master students utilize various research and characterization tools in their work, such as electrochemical apparatus, mechanical testing equipment of various sizes and scales, high-temperature facilities and surface-treating equipment, hydrogen compatibility testing equipment (figure below). Electron microscopes including TEM, FIB, 3D-APT are usually used for in-depth study of surface and structural features.  

Research Areas

1. Steels and alloys resistant to hydrogen embrittlement

2. Environmental damages (natural conditions, high temperature and pressure, corrosion environment) of materials with its prevetion methods 

3. Service safety and life prediction of metal structures under stress and chemical actions

4. Advanced corrosion-resistant steels and alloys, such as high-performance sucker rod steels and hydrogen-tolerant steels

5. Organic / inorganic protective coating

6. Performance improvement through microstructural modification and surface enhancement

7. Materials produced by fusion welding and laser impact welding

8. Al composites and ODS alloys

Research Highlights

1. Fabrication of nanocrystalline structure using surface mechanical attrition treatment to improve in-service performance.

To address the problem of intergrannular cracking and resistance in high-temperature steam, 316L stainless steel is processed to produce a graded sub-surface grain size, down to 30 nm. （M. Ran, C. Zhang, L. Wen, H. Zhou, W. Zheng. Effect of surface mechanical attrition treatment on stainless steel corrosion. Surface Engineering, Published online: 09 Jul 2020.）

2. Laser impact welding technique. This is a novel method of joining dissimilar metals. TEM was used to study the joining mechanism. The EBSD image shows the significant microstructure evolution along the joining interface. (H. Wang, D. Liu, J. Lippold, G. Daehn, Laser Impact Welding for Joining Similar and Dissimilar Metal Combinations with Various Target Configurations, Journal of Materials Processing Technology, 2020, 278,116498)

3. The effect of thermal ageing on the stress corrosion cracking (SCC) susceptibility of 310S stainless steel in the supercritical water. The high-temperature thermal treatment rendered the 310S immune to either intergranular or transgranular SCC under the supercritical water exposure conditions. (Yinan Jiao, Wenyue Zheng and Joseph R. Kish, Corrosion Science, Volume 135, 1 May 2018, Pages 1-11)

(a) SA sample                (b) sensitized sample              (c) TT sample.  

Boxes in (c) demarks σ phase precipitate in plan view.

4. Stress-corrosion cracking (SCC) in X52, X60, and X80 pipeline steels vary with electrochemical potential, transitioning from anodic dissolution under OCP to hydrogen induced cracking under cathodic conditions. Using static and slow-strain tensile testing, along with tapered samples to measure stress threshold values, SCC in pipeline steels under various conditions are re-produced and studied so as to develop measures to control this type of failures. (Zhang C, Wang H, He Y, Zheng W, Wang Y. Electrochemical potential dependence of SCC initiation in X60 pipeline steel in near-neutral pH environment. Journal of Materials Research and Technology. 2023 Nov 1;27:4950-61.)

(a) Transgranular SCC in an X-80 steel after 110 days testing; (b) The stress threshold values of X60 steel change with different electrochemical potentials.

5. Microstructure of sucker rod steels: Adding Mo, Cr, V, Ni, and Nb to low carbon steel and performing normalizing and tempering can produce granular bainite or a large quantity of dispersed precipitate so that the steel has better structural stability and anti-H2S performance. Grannular bainite-ferrite-precipitate complex structure has high toughness. (Zhou H, Sun X, Tong Z, Cheng G, Xu B, Xiao X, Wang Q, Ran M, Ding H, Zheng W, Chen X. Effects of tempering temperature on the precipitation behaviors of nanoparticles and their influences on the susceptibility to hydrogen embrittlement of a Cr–Mo–V steel. International Journal of Hydrogen Energy. 2024 Jan 2;50:254-69.)

6. By revealing the impact of cooling time on the microstructure and hydrogen embrittlement susceptibility of the CGHAZ in CrMo steel,this study provides insights for optimizing heat treatment processes, reducing material brittleness in hydrogen-rich environments, and minimizing crack initiation risks, thereby enhancing the reliability and safety of critical components in hydrogen-bearing media.( Tong Z, Wen Q, Wang H, Zhou H, Zheng W. Effect of heat input on the microstructure and hydrogen embrittlement susceptibility of the coarse-grain heat-affected zone of CrMo steels generated using a Gleeble 3500 welding simulator. Engineering Failure Analysis. 2024 Dec 1;166:108868.)

The crack initiation sites are located at different interfaces, including the martensite lath, cementite/ferrite interface, and martensite/ferrite interface.

7. The effect of loading rate on the fracture toughness of AISI 1020 and X80 steels was investigated through experimental testing and numerical simulations. The results suggest that current hydrogen compatibility testing standards may not adequately capture material degradation at slow loading rates, potentially posing safety risks for pipeline steels.( Wang H, Zhang C, Ma H, Tong Z, Huang Y, Jin Y, Su C, Zheng W. Assessing the effects of loading rate on fracture toughness of AISI 1020 and API 5L X80 steels with hydrogen Charging: Experimental and numeric simulation study. Engineering Fracture Mechanics. 2024 Dec 25:110771.)

The impact of loading rate on fracture toughness (AISI 1020 and X80), crack initiation site morphology, and hydrogen concentration distribution in X80.

• Professor Wenyue Zheng

• Associate Professor Huiming Wang

• Associate Professor Hongyu Zhou

• Assistant Professor Yinsheng He