We were introduced to ceramic composites in the morning, particularly in the defense application. Then our friendly researcher Dr Du Zehui presented us with a sample of composite that looked exceptionally smooth, well at least from our eyes. She then led us into a super secret room...
Opening the doors, we were surprised by a giant machine that looked like something out of a sci-fi film. 1 meter by 1 meter by 2.5 meter, is was an elaborate machine with probes, tubes and wires protruding out from the center. The machine, called a Scanning Electron Microscope (SEM), could view images of the material with a magnification of up to 120,000 times! Basically, you could see things far smaller than any conventional microscope can ever offer. After a little research, we learnt that the SEM works on the basis of shooting electrons rather than using light as used in a conventional microscope. Apparently, we were also told that the machine had to be located on the ground floor as any vibration from even the mere act or walking in the room could disturb the position of the sample.
On viewing the magnified sample, we were so surprised! There were so many scratches and protrusions on the surface on the material. It all seemed like a miracle, the work of science technology to bring us something so surreal. Later, we were told that the machine was not only a SEM, it is also able to coat the sample in a thin protective layer of platinum and even etch into the material with an ion beam to produce a cross-section of the sample. Amazing! Initially during the etching process, we could see the fibres embedded in the ceramic but then it was promptly defaced by the pure power of the high-speed bombarding ions.
After lunch, we met up with Dr Li Jianzhang who introduced us to the manufacturing procedure in making ceramic composites. He brought us around the laboratory where he worked to view the furnace used to temper the samples in order to harden the material and prepare it for its upcoming torture test. It can heat the samples to 1500°C! We were then shown a giant roll of carbon fibre used by the researchers in making ceramic fibre composites as well as several sample of composites from other researchers. We also had a brief discussion with him regarding the life of a research scientist where we gained new insights about his field of work.
After lunch, we met up with Dr Li Jianzhang who introduced us to the manufacturing procedure in making ceramic composites. He brought us around the laboratory where he worked to view the furnace used to temper the samples in order to harden the material and prepare it for its upcoming torture test. It can heat the samples to 1500°C! We were then shown a giant roll of carbon fibre used by the researchers in making ceramic fibre composites as well as several sample of composites from other researchers. We also had a brief discussion with him regarding the life of a research scientist where we gained new insights about his field of work.
Surface of the ceramic composite
Tiny particles on the surface of the material, high magnification!
Minuscule flakes of silver on the ceramic with sizes for reference
Thin, protective layer of platinum deposited on the surface prior to etching
Microscopic particles of platinum!
After etching with ion beam
After polishing
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