JMatPro計(jì)算原理探討.ppt

1、JMatPro計(jì)算原理探討,動(dòng)態(tài)物理模型的建立 強(qiáng)大的金屬材料數(shù)據(jù)庫(kù) 廣泛且經(jīng)實(shí)驗(yàn)驗(yàn)證的計(jì)算結(jié)果,Modelling properties and behaviour: JMatPro 材料性能模擬： JMatPro,3.1 Thermodynamic Calculations: Background 熱動(dòng)力學(xué)計(jì)算原理,Basic equation for the Gibbs Energy of a multi-component Solution Phase 多元合金固溶相吉布斯自由能基本方程,Gibbs energy of pure components 純組元的吉布斯自由能,Ideal

2、entropy 理想狀態(tài)下的焓,Interaction terms(Based on pairwise interactions) 相互作用項(xiàng)（基于兩兩之間相互作用）,3.2 Phase Transformation Kinetics:Model 相轉(zhuǎn)變動(dòng)力學(xué)模型:(用于鋼的),General Equation for TTT calculation is after Kirkaldy et al. (TTT計(jì)算的一般方程： Kirkaldy et al.), = 2(G-1)/2, is an empirical coefficient, G is the ASTM grain size,

3、D is an effective diffusion coefficient, T is the undercooling, q is an exponent,dependent on the effective diffusion mechanism and x is the fraction transformed. ( = 2(G-1)/2, 是一個(gè)經(jīng)驗(yàn)系數(shù)，G是晶粒尺寸，D是有效擴(kuò)散系數(shù)， T 是過(guò)冷度， q 是一個(gè)取決于有效擴(kuò)散機(jī)制的指數(shù)。 X是轉(zhuǎn)變的百分?jǐn)?shù)),3.2. 1 Martensitic transformations 馬氏體轉(zhuǎn)變,3.2.2 Phase Transfor

4、mations (TTT/CCT diagrams) 相轉(zhuǎn)變（TTT/CCT相圖）,Calculated TTT diagrams for U720 and U720LI with experimental results of Keefe et al. superimposed.,對(duì)U720 和 U720LI 所計(jì)算的TTT曲線與Keefe et al. 的實(shí)驗(yàn)結(jié)果比較,3.2.3 Phase Transformations (g/gcoarsening) 相轉(zhuǎn)變（ /晶粒的長(zhǎng)大 ）,晶粒的計(jì)算長(zhǎng)大率與實(shí)驗(yàn)得到的長(zhǎng)大率的比較,3.2.2 Phase Transformations (TTT/

5、CCT diagrams) 相轉(zhuǎn)變（TTT/CCT相圖）,718,Calculated TTT diagram for the single crystal alloy RR2071 with experimental results of Rae at al. superimposed,3.2.2 Phase Transformations (TTT/CCT diagrams) 相轉(zhuǎn)變（TTT/CCT相圖）,RR2071合金計(jì)算的TTT曲線與Rae at al.的實(shí)驗(yàn)結(jié)果的比較,3.3 Background to Property Calculations 物理/熱物理性能計(jì)算背景知識(shí),Pr

6、operty of a Solution Phase 固溶相性能,Property of pure components 純組元時(shí)的性能,Interaction terms(Based on pairwise interactions) 相互作用項(xiàng)（基于相與相兩兩之間相互作用）,3.4 Mechanical Properties 機(jī)械性能,Two types of strengthening mechanism are treated. 可考慮兩種強(qiáng)化機(jī)制 Solid solution strengthening. 固溶強(qiáng)化 Particle strengthening. 第二相粒子強(qiáng)化,3.

7、4.1 Mechanical Properties (Precipitation Hardening) 機(jī)械性能（析出強(qiáng)化）,The yield strength of an alloy hardened by g particles can be given by the equation below for small particles 微小粒子對(duì)合金的屈服強(qiáng)度的強(qiáng)化效果可用以下方程來(lái)衡量,YS0 and YS1 = yield stress of the matrix and alloy M = Taylor factorb = burgers vector,A = shape dep

8、endent constant d = ppt. diameter = line tension of a dislocation f = vol fraction = APB energy YS0 和 YS1 = 晶格屈服強(qiáng)度和合金屈服強(qiáng)度 M = 泰勒系數(shù) b = 柏氏矢量 A = 形狀因子常量 d = 析出粒子直徑 = 位錯(cuò)的線張力 f = 體積分?jǐn)?shù) = APB 能量,For larger particles the equation below can be used 對(duì)于大尺寸的粒子，強(qiáng)化效果用下面方程來(lái)衡量, = constant that accounts for repulsi

9、on of dislocations within the precipitates (essentially an empirically adjustable parameter). =一個(gè)表明析出物內(nèi)部位錯(cuò)間斥力的常數(shù)（實(shí)質(zhì)上是一個(gè)經(jīng)驗(yàn)系數(shù)）,3.4.1 Mechanical Properties (Precipitation Hardening) 機(jī)械性能（析出強(qiáng)化）,3.4.2 Mechanical Properties 機(jī)械性能,屈服強(qiáng)度的計(jì)算值與實(shí)驗(yàn)值的比較,3.4.3 Comparison of Mechanical Properties for Ni-based Supera

10、lloys 鎳基超合金機(jī)械性能實(shí)驗(yàn)與計(jì)算值的比較,3.4.4 Ageing Response of a Ni-based Superalloy (combining coarsening and pptn hardening) 鎳基超合金時(shí)效效應(yīng)（綜合晶粒長(zhǎng)大和析出強(qiáng)化）,3.5 High Temp Mechanical Properties (creep)高溫機(jī)械性能（蠕變）,General Creep Equation蠕變一般方程,A = Material constant D = effective diffusion coeff SFE = stacking fault energyG

11、 = shear modulus b = burgers vector = applied stress o = back stressE = Youngs modulus m = 3n = creep exponent,A = 材料常數(shù) D = 有效擴(kuò)散系數(shù) SFE = 層錯(cuò)能 G = 剪切模量 b = 柏氏矢量 = 外加應(yīng)力 o = 背應(yīng)力 E = 楊氏模量 m = 3n = 蠕變指數(shù),3.5.1 High Temp Mechanical Properties (creep)高溫機(jī)械性能（蠕變）,蠕變率的計(jì)算值與實(shí)驗(yàn)值的比較,As rupture strength is an altern

12、ative design criterion in many practical cases, the calculation procedure has been extended to include this property by using an inverse relationship between stress rupture life and secondary creep rate 在許多實(shí)際情況中，斷裂強(qiáng)度是一個(gè)可供選擇的設(shè)計(jì)標(biāo)準(zhǔn)。我們的軟件現(xiàn)在已經(jīng)能夠計(jì)算蠕變強(qiáng)度，這是通過(guò)利用蠕變斷裂應(yīng)力與蠕變率的對(duì)立關(guān)系間接得到的。,3.5.2 High Temp Mechanica

13、l Properties (creep)高溫機(jī)械性能（蠕變）,Comparison between experimental and calculated 1000hr rupture strengths for various wrought Ni-based superalloys,3.5.3 High Temp Mechanical Properties (creep)高溫機(jī)械性能（蠕變）,成分不同的各種鎳基超合金1000小時(shí)斷裂強(qiáng)度實(shí)驗(yàn)值與計(jì)算值的比較。,Comparison between experimental and calculated rupture life for va

14、rious single crystal superalloys,3.5.4 High Temp Mechanical Properties (creep)高溫機(jī)械性能（蠕變）,各種單晶超合金斷裂壽命的實(shí)驗(yàn)值與計(jì)算值的比較。,The creep calculations have been combined with the earlier low temperature yield stress calculations to model the flow stress of Ni-based superalloys at raised temperatures. 蠕變計(jì)算已經(jīng)綜合了早期低溫

15、屈服應(yīng)力計(jì)算，用來(lái)模擬鎳基超合金隨溫度升高時(shí)的流體應(yīng)力。,3.6 High Temp Mechanical Properties 高溫機(jī)械性能,The decay in RT yield stress with is well matched using an equation of the following type 高溫情況下，室溫屈服應(yīng)力的衰減與下面方程所給出的結(jié)果相吻合。,where and are constants directly related to RT and the value of Q, which is determined empirically through

16、regression analysis.,3.6 High Temp Mechanical Properties 高溫機(jī)械性能,在這里，和 都是與室溫強(qiáng)度RT 和激活能Q值直接相關(guān)的常量。Q值的大小一般是通過(guò)回歸分析憑經(jīng)驗(yàn)來(lái)確定的。,As the temperature is raised to high levels the alloy will yield via creep when the strain rate of the mechanical test is equal to or slower than the creep rate at the testing tempera

17、ture. 當(dāng)溫度升到較高的檢測(cè)溫度下，試驗(yàn)機(jī)的拉伸速率等于或小于蠕變速率時(shí)，合金將發(fā)生蠕變屈服。 This can be combined with the previous relationship,3.6 High Temp Mechanical Properties 高溫機(jī)械性能,to give mechanical properties from RT to the melting point 把蠕變效應(yīng)和其它因素結(jié)合起來(lái)，這樣我們就可以給出從室溫到材料熔點(diǎn)區(qū)間范圍內(nèi)材料的機(jī)械性能。,Comparison between experimental and calculated yield stress for Nimonic 75 and 105 as a function of temperature.,3.6 High Temp Mechanical Properties 高溫機(jī)械性能,75和105鎳基合金實(shí)驗(yàn)與計(jì)算情況下強(qiáng)度隨溫度的變化的比較,Comparison between experimental and calculated yield stress