Chunjing Li

Fabrication Technique Development of Dual Functional Lithium Lead Test Blanket Module

Abstract China Low Activation Martensitic (CLAM) steel has been developed at Institute of Nuclear Energy Safety Technology under wide collaboration. Fabrication techniques for test blanket modules (TBMs) are being developed, and a 1/3 scale prototype is being fabricated. A 1/3 scale first wall (FW) mockup was fabricated by a one-step hot isostatic pressing (HIP) method with CLAM steel rectangular tubes and plates. Two cover plates and type L cooling plates were produced with strips and grooved plates using electron beam welding (EB) and HIP diffusion bonding. Also, the assembly routine of the FW cover plates and cooling plates and four back plates were pre-tested using solid plates. And, the FW, cooling plate and cover plates were non-destructively tested using dimensional measurements and ultrasonic wave tests, which showed preliminarily the feasibility of the fabrication process.

Influence of Interfacial Oxidation on the High-Heat-Flux Performance of HIP-Manufactured Flat-Type W/Cu Plasma-Facing Components for EAST

Abstract A hot isostatic pressing (HIP) route has been developed by the Institute of Plasma Physics of the Chinese Academy of Sciences in collaboration with the Advanced Technology & Materials Co., Ltd. for bonding W/Cu tiles to Ni-electroplated CuCrZr heat sinks. During high-heat-flux testing, in the initial stage, Cu/Ni interfacial debonding was observed. Careful analyses indicated that interfacial oxidation during encapsulation for HIP processing using tungsten inert gas (TIG) welding was the main cause of the limited fatigue lifetime. Copper oxides formed during the TIG encapsulation do not decompose during HIP at 600°C. As a result, weak bonding and even some microcracks were generated, and unfortunately these microcracks could not be detected by current industrial ultrasonic probes. An oxidation-free encapsulation technique, suitable for batch processing, has been developed to achieve a thermal fatigue lifetime of more than 1000 cycles at a heat load of 5 MW/m2 for the components.

Influence of Quenching Process on Structure and Microhardness of CLAM Steel

Abstract In order to investigate the effect of austenitizing temperature and holding time on the martensitic lath width and microhardness, the microstructures of China Low Activation Martensitic (CLAM) steel_(HEAT 0603A) specimens with different heat treatments were analyzed by scanning electron microscope (SEM), and the martensitic lath widths were gained. Besides, the microhardness was obtained by Vickers hardness tests. Based on these results, the relationship between microhardness and heat treatment was given. Taking all factors into consideration, quenching at 1253K for 30min was the optimum heat treatment condition for CLAM (HEAT_0603A). Further study and investigation, such as a series of verification tests etc., will be carried out in the near future.