Lumber is a kind important but one of renewable resources, can last what use a level integratedly to matter to global economy and society of lumber development. But in recent years, resource of natural forest material is in short supply inside alive bound limits, basically be lumber resource changed direction artificial forest. As a result of artificial Lin Lun cut down period is short, place of Zhong Youling material occupies lumber proportion is larger, semi-cellulose and wooden element content are high, material is qualitative poorer, case and density is low, dimension stability and wear are poor, restricted its to use an approach consequently.

Researcher ever tried all sorts of method to increase the dimension stability of lumber, if be in lumber surface cover with paint or of the stickup material that stick a face outside bag law, and more it is to use drug dip to note a way, close the hydroxyl of lumber, what reduce lumber thereby is hygroscopic, improve its dimension stability.

However, recently 20 years, as life quality rise, abroad has all sorts of reports, raise doubt to making chemically drug handles the security of material. Current, the United States and European Union are making a few provisions, in the regulation the circumstance restricts chemical drug to handle the use of lumber, especially furniture of table of playground, board, picnic, fence, courtyard, scenic spot scenery and children are easy the circumstance of bring into contact with. The European Union will be carried out in the round " the injunction that about restricting course arsenic the lumber of anticorrosive processing enters the market " , covered export lumber and all sorts of wood. Similar restriction also has a regulation in Japan and Australia. Each country protects byelaw severely, promoted the research that safety and target get used to and development. In all sorts of processing technologies, the wood products that is not chemical drug processing is obtaining vaster and vaster market space, among them the technology of superhigh temperature heat treatment of lumber also held significant position.

One. Heat treatment of lumber superhigh temperature reachs craft:
General wood is dry in, temperature <100 is spent for convention dry, 100- - 150 degrees are high temperature dry, > 150 degrees are superhigh temperature dry. The heat treatment of lumber uses wood namely be close to or prep above in environment of 200 degrees content of superhigh temperature low oxygen, after handling proper time continuously, make lumber medium semi-cellulose degradation, the hydroxyl in lumber cell wall decreases, the moisture absorption function of lumber drops, dimension stability and be able to bear or endure sex of biology broken annulus gets ameliorative. Accordingly, the lumber of superhigh temperature heat treatment is regarded as a new-style material to be paid close attention to extensively.

Processing technology is crucial to the influence of material, if handle temperature, processing time, heat tree of rate, lumber is planted, the weight of test specimen and dimension, first the parameter such as moisture content, can affect the final performance of the product. Handling technology basically is the use purpose that depends on a product surely really, in bibulous function improvement and mechanical function are reduced between optimize, find acceptability balance place. Differ according to what processing uses medium, main component is processing technology 3 kinds.
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