Study On Key Technology Of Efficient And Energy-saving Nitriding Heat Treatment Furnace

How to nitride parts economically, security, energy-savingly and efficiently, is always one of the long-term problem discussed by the users and also heat treatment technology researchers both at home and abroad.In recent years, some of the domestic and foreign researchers carry on some fruitful studies aim at problems such as the low thermal efficiency in nitriding process, insufficient idea of permeability nitrogen layer surface, as well as the vacuum permeability nitrogen furnace thermal field tank, and obtain some new methods and technology. For example, the method makes use induction heating temperature rise faster and higher thermal efficiency; An automated control technology in order to shorten into, discharging time; Through optimization, thinning vacuum muffle tank wall thickness to improve heating efficiency, etc. These new technologies have their method although characteristics, and to a certain extent, improve the vacuum heat-treatment nitriding efficiency, but also exist such problems, usually not operation cost is exorbitant, poor reliability is safe.This topic based on the target of nitriding parts economically, efficiently and energy-savingly,come up with a new technology of ultrasound strengthening nitriding heat treatment"that is economic,safe,energy-saving and efficient through the research,and on the basis,do some reliability optimal designs on the key parts of the nitriding furnace.The main research contents of this paper are as follows:Chapter One: IntroductionDiscussed the research status of nitriding technology at home and abroad in recent years through investigation and study, analyzed their advantages and disadvantages from the perspectives of process and structure, with a key discussion on the problem of how to improve the efficiency of nitridation, and also put forward the main content of this topic. Chapter Two: Conceptual design of energy-saving and efficient nitriding furnaceI summarize the advantages and disadvantages of all kinds of the nitriding furnaces through the study and research on the structure of nitriding furnace both at home and abroad. And then put forward a new scheme on the ultrasound strengthening nitriding heat treatment of workpiece through the analysis.Chapter Three: The construction of ultrasound strengthening urge permeability nitride reaction kinetics modelFirst of all, put our hands to thermal and chemical reaction mechanism of vacuum nitriding, and through the study of workpiece chemical heat treatment urge permeability effect of ultrasonic, we can realize that ultrasound role may accelerate nitride reaction rate and improve the efficiency of nitridation.Through the research I deduced the equation betweenω, the ultrasound processing angular frequency,ρ, the density of ammonia in reaction vessel, and R e, the active radius of active N atom in reaction atmosphere, and when ultrasonic frequency equals to the natural resonant frequency of this active N atom, ultrasonic and N atom can achieve the most efficient energy coupling, produce intense ultrasonic irradiation strengthening infiltration nitrogen phenomenon, and on this basis constructed "ultrasound strengthening nitride reaction kinetics model".Chapter Four: Structure design and performance simulation of the ultrasound nitriding reactorThrough the related problems design of ultrasonic transformers in the analysis, firstly make sure that strengthening the shape of infiltration nitrogen ultrasonic transformers in luffing rod structure, the design calculation. Then use of ANSYS finite element analysis software designed by the compound ultrasonic transformers modal and resonant response analysis, the simulation, the conclusion compound ultrasonic transformers in design, the resonance frequency of the output terminal with maximum amplitude, namely corresponds with the design results.Chapter Five: Structure reliability and optimal design of the nitriding furnace's muffleThe chapter has adopted the conventional design, the reliability-based optimization design based on ANSYS parametric language and the optimized design three involved module for nitriding furnace design method of the muffle tank design, compared with engineering practice again determined muff cans for the design of 7 mm wall thickness.Chapter Six: Summary and ProspectSummarize the content of the preceding chapters, and put forward some problems exist in this study as well as the direction of the later development.The innovations in this subject:(1) Put forward a new process called "ultrasound strengthening nitriding heat treatment", which is relatively economic, safe, and efficient through the research.(2) Constructed "the kinetics model of ultrasound strengthening nitride reaction" through the research.(3) Utilize modern design method to conduct an optimal design on the key structure of heat treatment furnace-the structure of ultrasonic transducer and muffs cans, with the above research as the foundation,designed a new kind of energy efficient ultrasonic nitriding heat treatment furnace.