Z.H.Li
,
X.P.Liu
,
Y.Gao and Z.Xu Research Institute of Surface Engineering
,
Taiyuan University of Technology
,
Taiyuan 030024
,
China
金属学报(英文版)
It, ageing high speed steel (AHSS) with high cobalt, has a strong ability of age hardening. However, it has two disadvantages, One is short of toughness, the other is its high price because of its too much alloy content especially cobalt. All of these effect on its widespread using. Now there is a new method without the two flows to form this steel in the surface of ingot iron by use of double glow plasma surface alloying technique.In this paper, the following three parts are introduced: the metallurgical process of this surface ageing high speed steel (SAHSS), the micro structure of the alloying layer, the alloy distribution in the layer. By using the designed source pole, the special alloying process, the required surface alloying content, just like the AHSS—Co23W11Mo7 can be achieved in the surface layer. This new method has wide prospect in the fields of tools, moulds and other wear resisting fields.
关键词:
SAHSS
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null
,
null
X.P.Liu
,
M.Z.Cao
,
R.Yang
金属学报(英文版)
The effect of pre-strain on phase transformation of TiNi shape memory alloy film was studied by differential scanning calorimeter measurement(DSC).Compared with undeformed TiNi film,the reverse transformation of pre-strained specimens was elevated to a higher temperature on the first heating,but martensite and reverse transformation on subsequent thermal cycles occurred at a lower temperature.The evolution of transformation behavior in pre-strained TiNi film was related to the change of elastic strain energy,irreversible energy and internal stress field.
关键词:
shape memory alloy
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null
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