【正文】
采用熱分析儀 ,分析不同塑 料試樣分別在惰性氣氛和氧化性氣氛中 恒速升溫 條件下熱失重過(guò)程中的吸熱與放熱情況。 magic properties 16 論文題 目: 廢塑料作為高爐噴吹輔助燃料的基礎(chǔ)性研究 Fundamental Study of Injecting Plastic Scrap as Assistant Fuel into BF 研究生姓名: 陳偉鵬 導(dǎo)師姓 名: 朱 蒙 教授 專 業(yè): 材料加工工程 摘 要 : 本文對(duì)廢塑料作為高爐噴吹輔助燃料做了基礎(chǔ)性的研究。 particle size。 關(guān)鍵詞: 粘結(jié) NdFeB 粘結(jié)劑 粒度分布 成型壓力 磁性能 ABSTRACT To make exertions of the rare earth advantage of our country and to improve the magic industry, this paper presents parative systematic research of problems in the preparation of economical mould pressing bonded NdFeB permanent mags. The bonded mag from rapid quenched NdFeB has been produced, and the influence of the technique factors such as coupling agent, coupling process, powder particle size, binder, solidification process, formation process on its properties has been analysised by means of NIM2020H magic properties analysis, PW1700 xray diffraction, and QUANTA400 SEM, etc. From a lot of tests, the bonded NdFeB mag with high properties have been prepared by rapid quenched powder, and the mechanic and magic properties with Br=, Hcj=721kA?m,(BH)max=86kJ. Several formulations are given in the article. They show many relationships, such as the relationship between ponent ratio and geometrical size of institutes, the relationship between mag powder and the volume percentage of mag powder, and the relationship between powder movement and density. These formulations make things convenient for the predesign of mag. Experiments proved that the mixture of different size of powder can improve its properties. It is better to mix 100 mesh and 80 mesh as 1:, then mix the former mixture with 200 mesh with ratio as 1:. When the content of binder was changed, the magic properties are following the same law as the density. The best range of the content of binder is 3%~ 4%(Wt.). Moulding pressure is the most important factor, high pressure can increase its properties. But the die would be destroyed by pressure, so the best pressure is 730Mpa. Key words: bonded NdFeB。與磁性相體積分?jǐn)?shù)變化趨勢(shì)相同,磁體性能隨粘結(jié)劑含量增加呈現(xiàn)先提高后降低的規(guī)律,當(dāng)粘結(jié)劑與磁粉質(zhì)量比為 3%~ 4%時(shí)磁性能最佳。 通過(guò)理論研究,得到了粘結(jié)磁體原料配比與組分參數(shù)間的關(guān)系、磁性能與組分組成間的定量關(guān)系表述、壓制過(guò)程中粉末的運(yùn)動(dòng)規(guī)律、磁體在空間所產(chǎn)生磁場(chǎng)的理論公式。在不同工藝條件下 15 制備粘結(jié)磁體,利用 NIM2020H磁性能測(cè)試儀、 PW1700x 射線衍射儀和 QUANTA400 型 掃描電子顯微鏡等測(cè)試分析手段,研究了各個(gè)工藝參數(shù)對(duì) NdFeB 磁性材料磁性能的影響。依據(jù)這樣的曲線規(guī)律,很容易制得室溫附近的成分不同的鈣鈦礦樣品,并能預(yù) 測(cè)已知成分 的 鈣鈦礦樣品的居里溫度。 采 用最 佳 水熱 條 件一 步 直接 合成 的, 為 很純 的鈣鈦礦,在 , 其居里溫度 Tc為 323K,最大 adT?為 。 同時(shí)找到了影響合成結(jié)果的關(guān)鍵性因素 —高壓釜的密封性,最終改進(jìn)了工藝:將最初的 ―水熱 —熱處理 ‖合成工藝變?yōu)橐徊剿疅峒纯珊铣伞? 與其它磁致冷工質(zhì)相比,稀土錳鈣鈦礦材料 具 有以下優(yōu)勢(shì):低磁場(chǎng)下其磁熱效應(yīng)較高,而且化學(xué)性質(zhì)穩(wěn)定、居里溫度可調(diào)、電阻率大、成本低,是室溫制冷的理想工質(zhì)。 內(nèi)蒙古科技大學(xué)與包頭稀土研究院合作 6 年,進(jìn)行室溫磁致冷技術(shù)開發(fā)研究 。 Crystallization heat treatment。 By the high temperature vacuum mould technology, the density of nanoposite permanent magic alloys was improved and the volume fraction of mags was reduced. At the same time, the orientation of crystalline can wheel in the process of dieupsetting. This will be benefit for permanent alloys magism. Key words: NdFeB permanent mags。 Meltspun alloys include three parts: the amorphous area, the crystal area of pole and the equalaxis crystal area. When the velocity is 21m/s of meltspun, the percent of the crystal area of pole is plentiful, the up growth of pole crystal e into being the texture. The result of experiment stated that this texture is the same to easy magization orientation of permanent magic alloys。高溫真空模壓成型工藝提高永磁體密度,減小了孔洞體積率,同時(shí)模壓的過(guò)程中,永磁合金磁粉晶粒會(huì)有一定取向的轉(zhuǎn)動(dòng),有利于提高永磁體的 磁性能。 實(shí)驗(yàn)結(jié)果表明: 用 Pr元素代替 NdFeB永磁合金中 Nd元素,提高了永磁合金的矯頑力 ,最大值達(dá)到了 1227KA/m;熔體真空快淬永磁合金的組成有三部分:非晶區(qū)、柱狀晶區(qū)和等軸晶區(qū)。利用透射電子顯微鏡( TEM)進(jìn)行了顯微組織分析,確定了在永磁合金的組織中有晶體和非晶共存,通過(guò)電子衍射對(duì)永磁合金中相的晶體結(jié)構(gòu)進(jìn)行了分析,同時(shí)也研究了非晶組織的轉(zhuǎn)變過(guò)程中相的變化對(duì)磁性能的影響。 實(shí)驗(yàn)通過(guò)熔煉技術(shù)、真空快淬技術(shù)、真空晶化熱處理技術(shù)及 模壓成型技術(shù)制備了各向同性的粘結(jié)永磁體,使用 BH 磁滯回線測(cè)量?jī)x測(cè)量永磁體的磁性能。要制備高性能的粘結(jié)永磁體必須要有高性能的磁粉。但是,粘結(jié)永磁體一個(gè)缺點(diǎn)就是跟燒結(jié)永磁體相比,性能較低。其結(jié)果可以為板型控制和工作輥壽命計(jì)算分析提供理論依據(jù)。在工作輥熱應(yīng)力計(jì)算中,采用 Solid45 結(jié)構(gòu)單元進(jìn)行解析,把溫度作為載 荷施加到結(jié)構(gòu)單元上,得到工作輥徑向、軸向、剪切方向以及 Von Mises 等效熱應(yīng)力的熱應(yīng)力等值線分布圖。本文就是利用 ANSYS 有限元分析軟件對(duì)熱軋帶鋼工作輥的溫度場(chǎng)和熱應(yīng)力進(jìn)行解析。工作輥溫度場(chǎng)的求解方法有解析法、數(shù)值法和實(shí)測(cè)法等,但由于熱軋工作輥工作條件極其惡劣和復(fù)雜,解析法和實(shí)測(cè)法等都沒(méi)有令人滿意的結(jié)果。因此,定性和定量確定熱應(yīng)力顯得尤為重要,準(zhǔn)確計(jì)算工作輥的溫度場(chǎng)是計(jì)算其熱應(yīng)力的前提。同時(shí)工作輥由于受周期性溫度的作用,特別是工作輥表面受到瞬態(tài)周期性的熱沖擊,內(nèi)部產(chǎn)生熱應(yīng)力。 Web。 Product development。 基于 Web 的面向產(chǎn)品開發(fā)過(guò)程的 客車產(chǎn)品數(shù)據(jù)管理系統(tǒng)的建立對(duì)客車企業(yè)的信息化建設(shè)具有重要的意義,是客車企業(yè)技術(shù)部門實(shí)現(xiàn)資源共享、數(shù)據(jù)繼承以及并行工程的基礎(chǔ),它的實(shí)施將提升客車企業(yè)的技術(shù)管理水平,為企業(yè) CIMS 建設(shè)打好基礎(chǔ)。 8 在對(duì)客車行業(yè)產(chǎn)品開發(fā)部門進(jìn)行需求分析的基礎(chǔ) 上,運(yùn)用軟件工程方法,對(duì)系統(tǒng)進(jìn)行了分析與設(shè)計(jì),規(guī)劃了系統(tǒng)實(shí)現(xiàn)的網(wǎng)絡(luò)體系結(jié)構(gòu),并對(duì)其安全策略進(jìn)行了研究;利用成組技術(shù)及相似性原理,對(duì)客車零部件進(jìn)行了合理的分類,建立了客車零件數(shù)據(jù)庫(kù);應(yīng)用文檔管理的方法,對(duì)客車產(chǎn)品開發(fā)過(guò)程中的文檔進(jìn)行了分類管理,建立了圖文檔數(shù)據(jù)庫(kù);運(yùn)用 ASP 和 ODBC 技術(shù)對(duì)系統(tǒng)進(jìn)行了開發(fā),實(shí)現(xiàn)了客車產(chǎn)品數(shù)據(jù)的管理和查詢;考慮到該系統(tǒng)是面向產(chǎn)品開發(fā)過(guò)程的數(shù)據(jù)管理,其安全性的重要,建立了用戶管理子系統(tǒng),提高了系統(tǒng)的安全性。 最后對(duì)全文作了總結(jié),并提出了展望。 (3) 根據(jù)費(fèi)歇判別分析的基本原理提出了基于費(fèi)歇貢獻(xiàn)圖的過(guò)程參數(shù)診斷方法,并將該方法和主元貢獻(xiàn)圖方法應(yīng)用到四水箱過(guò)程進(jìn)行過(guò)程參數(shù)診斷;最后通過(guò)診斷結(jié)果比較這兩種方法的性能。本文的研究工作主要包括以下幾個(gè)方面: (1) 緒論中對(duì)質(zhì)量的概念以及質(zhì)量科學(xué)的形成和發(fā)展做了簡(jiǎn)單的介紹;接著分別介紹了單變量統(tǒng)計(jì)過(guò)程控制的一些方法,主元分析的基本理論和基于主元分析的多變量統(tǒng)計(jì)過(guò)程控制及其一些改進(jìn)方法;最后對(duì)統(tǒng)計(jì)過(guò)程診斷的發(fā)展?fàn)顩r作了簡(jiǎn)單的敘述。在質(zhì)量 控制過(guò)程中,當(dāng)發(fā)現(xiàn)質(zhì)量發(fā)生異常波動(dòng)時(shí) ,為了能夠及時(shí)調(diào)整過(guò)程參數(shù)使得生產(chǎn)過(guò)程恢復(fù)到正常狀態(tài),有必要利用質(zhì)量診斷方法對(duì)生產(chǎn)過(guò)程進(jìn)行診斷。 關(guān)鍵詞: 超磁致伸縮換能器;系統(tǒng)特性;數(shù)學(xué)模型;有限元分析;仿真模型;磁機(jī)耦合 ABSTRACT The giant magostrictive material is a new functional material, which has high magostriction、rapid response velocity、 great energy density, as well as big output force. Because of the choiceness properties of the GMM, many researchers of the world countries now have taken part in studying it. In the mean time, its corresponding theory and applications studies are being processed. In this thesis , the inputoutput characteristics of great magostrictive transducer are discussed. The purpose of reaseach is to get universal mathematical model of great magostrictive transducer, which can provide a theoretic basis for the design of magostrictive instrument . Firstly the thesis has a discussin about characteristic and performance of the giant magostrictive material 、the actuality of instrument exploitation and the state of academic studies in detail. Moreover, it has further discussions in the following aspects: 1. Simulate the influence that ΔE offect act on magostrictive rod by the limited c