冷轧压下率对连续退火Ti-IF钢组织和深冲性能的影响

以工业生产的Ti-IF钢热轧板为研究材料,结合连续热镀锌线的工艺特点,采用实验室冷轧、盐浴退火方法和金相、X射线织构测试和力学性能检测等分析手段,研究了冷轧压下率对组织、织构和深冲性能的影响规律。试验结果表明,随着冷轧压下率从60%提高到90%,冷轧态α取向线上的取向密度不断增强,主要形成了{223}〈110〉和{114}〈110〉织构,γ取向线上的{111}〈011〉和{111}〈112〉织构亦有所增强;退火后铁素体晶粒尺寸从9.0级细化到10.5级,导致强度(特别是屈服强度)有所增加,η_(90°)值有所降低。试验钢退火后仍具有较强的{223}〈110〉和{114}〈110〉织构,此外,随着冷轧压下率从60%提高到80%,{111}〈110〉和{111}〈112〉织构有增强的趋势,且{111}〈110〉织构比{111}〈112〉织构强,r_(90°)值有所提高;当冷轧压下率进一步提高到90%时,{111}〈112〉织构明显增强,但{111}〈110〉织构变化较小,导致{111}〈112〉织构比{111}〈110〉织构强,使r_(90°)值反而有所降低,这与γ织构分布变化导致制耳分布曲线由典型的4制耳特征转变为6制耳特征有关。     

退火工艺对CSP供冷轧原料的SPCC板性能和织构的影响

在试验室条件下，模拟了CSP热轧带钢供冷轧原料的SPCC级低碳钢板的罩式炉退火过程，分析了不同退火工艺对CSP热轧带钢供冷轧原料的SPCC板的深冲性能和组织的影响，研究了织构随升温速度变化的演变规律。试验结果表明随升温速度的降低，τm、△τ值都逐渐升高，τm为1．68，△τ达到0．68；变形织构{112}〈110〉变弱，表明降低升温速度可以消除变形织构，但速度低于40℃／h时消除作用就不明显。降低升温速度也可以使{111}〈110〉织构和{111}〈112〉织构的强度差增大。钢板△τ值的变化受多重因素影响，{111}〈110〉织构和{111}〈112〉织构的强度差可能是导致△τ值升高的原因之一。     

390MPa级超低碳BH钢织构演变规律

采用ODF织构分析方法,对390 MPa级超低碳BH钢板热轧、冷轧、退火过程织构演变规律进行研究,并对不同冷轧压下量和不同退火工艺织构进行分析。结果表明:经冷轧变形后的钢板有较强的择优取向,具有典型的{112}<110>和{111}<110>织构,形变织构中的不利织构{001}<110>较强;冷轧压下率为80%时再结晶退火后钢板具有较强的γ织构,{111}<112>织构取向密度高达11.7;退火温度和保温时间对α织构影响不大,提高退火温度和延长保温时间使γ织构增强,r值增加。     

无取向硅钢退火织构的演变与磁性能关系的研究

运用取向分布函数(ODF)分析了50W600电工钢不同退火工艺退火织构的演变及织构对电磁性能的影响,利用织构数据计算了无取向硅钢的磁晶各向异性能.研究表明,较高的退火温度或较长的保温时间,再结晶织构α线的取向密度下降,{100}〈011〉和{211}〈011〉取向密度急剧降低,γ线{111}〈112〉密度显著增加,晶粒取向绝大多数聚集在γ线{111}〈112〉取向附近;低温退火有助于提高无取向硅钢有利织构{100}〈UVW〉的占有率.磁晶各向异性能计算结果表明无取向硅钢也存在磁各向异性.     

Ti-IF钢组织织构演变规律

本文借助光学显微镜、X射线衍射仪（XRD）和电子背散射衍射技术（EBSD）对CSP流程生产Ti-IF钢的热轧、冷轧及退火板料分别进行宏观织构和微观织构的观察并研究其演变过程。结果表明,CSP工艺生产的Ti-IF钢的热轧织构比较散漫,开始形成较弱的γ纤维织构;冷轧织构主要是较强的γ纤维织构和较弱的α纤维织构,主要组分有{111}<110>、{111}<112>、{112}<110>、{001}<110>;退火织构以强烈的γ纤维织构为主,主要组分为{111}<110>、{111}<112>。     

(110)[110]Fe-Si单晶体的冷轧和再结晶

研究了(110)[110]Fe-Si单晶体的冷轧和再结晶。经过70—90%冷轧后,得到了强的{111}〈110〉和弱的{111}〈112〉加工织构,退火后得到了集中的{111}〈112〉再结晶织构。冷轧变形后,{111}〈112〉取向的地区比{111}〈110〉取向的地区先发生回复,{111}〈112〉取向的亚晶吞并滞后回复的地区而长大,成为再结晶晶核。这种再结晶织构的形成过程,可以概括地称为同位成核-选择生长。     

退火加热速度对CSP稀土冷轧钢板再结晶的影响

以CSP流程生产的稀土低碳钢板为试验材料,进行了不同加热速度下退火模拟试验,并结合光学显微镜和X射线衍射仪,分析了加热速度对退火试样织构和再结晶进程的影响。结果表明,加热速度从29℃/h提高到42℃/h再结晶开始温度提高了40℃,当加热速度提高到80℃/h,再结晶开始温度670℃;退火后形成了以{223}110和{111}110为主的再结晶织构,提高加热速度,α取向线上的{001}110和{111}110织构密度增强,{112}110、{223}110和{111}110均降低;γ取向线{111}112和{111}110织构密度以及密度差均降低。     

冷轧板再结晶退火中组织和织构演变的研究

薄板坯连铸连轧(CSP)热轧板料经热处理来适当调整组织后进行冷轧及退火,并运用电子背散射衍射(EBSD)技术研究了再结晶退火中组织和织构的演变.结果表明:发生再结晶的温度范围是530℃～590℃,590℃为完全再结晶温度;再结晶发生时冷轧变形基体和新晶粒取向的晶界角度差大约为25°～55°;{111}〈110〉、{111}〈112〉取向在再结晶初期和中期发生很大的变化,而{001}〈110〉、{112}〈110〉取向在再结晶后期才发生很大的变化;EBSD检测的结果分析可得{001}〈110〉、{112}〈110〉、{111}面取向储存的变形能依次增加.     

冷轧大压下量下新型无取向电工钢的退火组织演变

研究了冷轧大压下量,950 ℃退火时间对一种新型含铜无取向电工钢晶粒度和织构的影响.结果表明,大压下量冷轧,随压下量的增加,退火晶粒向γ线聚集,形成强{111}<112>织构.提高冷轧压下率,退火织构 {111}<100>,{110}<001>强度减弱,增加退火时间,退火织构{111}<110>,{100}<001>,{110}<001>强度变弱.采用87.5%冷轧压下率和950 ℃退火60 s,有利织构{100},{110}占有率最大.     

CSP流程供原料冷轧深冲板组织和织构演变

对某钢铁厂现场生产的SPCD板热轧、冷轧和退火板进行取样,在实验室分析了不同工序SPCD板的组织和织构,研究了其生产过程组织和织构演变.研究发现,SPCD板热轧织构较弱,但已表现出了α线织构和γ线织构的雏形,经过冷轧变形,γ线织构明显增强,且{111}<112>织构强于{111}<110>织构.经过退火后,与冷轧织构相比,退火织构γ线{111}<110>织构进一步增强,但{111}<112>织构强度有所降低.对比不同加热制度的退火工艺,采用双台阶退火工艺,能够得到更多的有利织构组分,从而有利于提升成品钢的成形性能.     

超纯铁素体不锈钢织构演变与成形性能的研究

系统研究了超纯铁素体不锈钢(w(Cr)=17%)沿钢板厚度方向各层织构的演变规律和不同精轧温度对织构演变及成形性能的影响规律。采用X射线衍射仪分析了宏观织构演变。研究表明: 热轧及退火后, 钢板表层以剪切织构为主, 中心层由?和?纤维织构组成; 冷轧后, 各层均由较强的?纤维织构和较弱的?纤维织构组成; 冷轧退火后各层均形成?纤维再结晶织构。与高温精轧相比, 低温精轧有利于冷轧退火板?纤维再结晶织构的强化、偏离{111}<112>组分的程度降低, 从而显著改善冷轧退火板的成形性能。     

润滑对3104铝合金板变形织构的影响

在无润滑(WOL)和润滑(WL)2种轧制条件下,分别对2.3 mm厚的热轧3104铝合金板进行不同压下量的冷轧.应用取向分布函数(ODF)定量计算和分析在不同轧制压下量下润滑对3104铝合金板材沿板厚方向织构演变的影响.结果表明:随着轧制压下量的增加,样品各层的织构组分强度均逐渐增加;无润滑轧制时样品表面层主要织构组分取向密度普遍高于相同压下量下润滑轧制时的取向密度.导致表面层织构组分增强的原因是摩擦引起应变状态改变的结果.     

CSP卷取温度对冷轧深冲钢板的影响

研究了热轧卷取温度对CSP(compact strip production)冷轧深冲板的性能、组织和织构的影响。CSP热轧板组织主要为多边形铁素体,随卷取温度降低,晶粒尺寸略有减小。660℃和680℃卷取的成品冷轧板组织为等轴晶粒,卷取温度不超过600℃时则以"饼型"晶粒为主。力学性能测试表明,低于600℃卷取的成品板屈服强度和抗拉强度较低,其加权平均塑性应变比(rm)可达到1.80以上,伸长率超过49%。随卷取温度升高,成品板的{001}〈110〉和{110}〈110〉织构的取向分布密度逐渐升高,{111}织构取向分布密度先升高后降低,{111}〈110〉和{111}〈112〉织构取向分布密度差值也是先升后降。     

高纯Cr17钢板厚方向织构演变、成形性能及表面皱折

以高纯Cr17铁素体不锈钢为实验材料,对比研究了热轧不退火、退火两种工艺对其板厚方向织构演变、成形性及表面皱折的影响。采用金相显微镜、X射线衍射技术及背散射电子衍射技术观察两种工艺条件下的组织和织构演变。结果表明:成品板各层织构特征存在显著差异,这是由于低温轧制过程中沿板厚方向不同应变状态导致的热轧织构梯度遗传所致。与热轧不退火相比,热轧退火有利于成品板各层γ纤维再结晶织构增强,偏离{111}<112>组分的程度减弱,α纤维织构弱化;有利于弱化成品板的带状晶粒簇,促使晶粒簇分布均匀分散。     

轧制工艺对薄带铸轧无取向硅钢组织性能的影响

利用光学显微镜、XRD、EBSD等研究了轧制工艺对薄带铸轧无取向硅钢组织、织构和磁性能的影响。研究表明,随热轧压下率增大,冷轧组织变形储能及剪切带的比例逐渐降低,冷轧板中α织构减弱,γ织构增强。退火板晶粒尺寸随热轧压下率增大而增加。热轧压下率为17%及40%时,退火织构以强的Goss织构及相对弱的{100}织构为主,热轧压下率达到55%后,退火织构为强的{115}<110>和{114}<371>织构,Goss织构和{100}组分明显减弱。随热轧压下率增大,退火板磁感值先升高后降低,铁损值先减小后增加。热轧压下率为40%时,退火板综合磁性能最优。     

Texture Evolution,Formability and Ridging Resistance of a Sn-bearing Ferritic Stainless Steel Under Different Hot Band Annealing Temperatures

The microstructure, texture evolution and spatial orientation distribution during cold rolling and the subsequent annealing as well as formability and ridging of a Sn-bearing ferritic stainless steel under different hot band annealing temperatures were investigated. The four hot bands with annealing temperatures of 900, 950, 1000 and 1050 °C were all cold-rolled to 80% reductions and then were annealed at the same temperature of 900 °C. The results show that optimizing hot band annealing process is benefi cial to reduce the amount of {001} 110 grains and weaken the texture intensity, and thus, to reduce ridging and improve formability. In the present study, the fi nal sheets with hot band annealing temperature of 900 °C possess small and inhomogeneous grains with a large amount of {001} 110 orientations, which deteriorates the formability and increases the ridging. In comparison, the fi nal sheets with hot band annealing temperature of 950 °C are comprised of uniform and equiaxed 111//ND(ND: normal direction) recrystallized grains with a high texture intensity favorable for the improvement in r value and surface quality. However, when hot band annealing temperature further increases to 1000 and 1050 °C, it shows a sharp decrease in r value and a remarkable increase in ridging as a result of a reduction in γ-fi ber texture intensity and an increase in grain size in the fi nal sheets. Suitable controlling and optimizing hot band annealing process is essential to improve the formability and reduce the ridging.     

Microstructure,texture and grain boundaries character distribution evolution of ferritic stainless steel during rolling process

In order to better understand the texture, microstructure and grain boundaries character distribution evolution of ferritic stainless steel, the texture, microstructure and grain boundaries character distribution of ferritic stainless steel (hot rolled sheet, cold rolled sheet and annealing sheet) with 11 wt%Cr content were studied using X-ray diffraction and electron back scattered diffraction technique. The texture of the hot and cold rolled sheets has a through-thickness texture gradient. In the center layer of the hot and cold rolling sheet, α-fiber texture was observed which was attributed to ideal plane strain deformation. Close to the surface a Gross orientation was detected which was attributed to shear deformation. During annealing, the γ-fiber was formed attributed to recrystallization process. The microstructure of the hot and cold rolled sheets was non-homogeneous through the sheet thickness, while, the microstructure of annealing sheets was homogeneous through the sheet thickness. Grain boundaries character distribution results show that there are many low angle grain boundaries in hot and cold rolled sheets and many high angle grain boundaries and coincidence site lattice after annealing. The above results indicated that the changes in texture are closely related to the grain boundaries type.     

Study on the cold rolling deformation behavior of polycrystalline tungsten

Tungsten is paid special attention due to its superior properties, especially in nuclear field. Meanwhile it is suitable for texture simulation investigation of BCC metals and alloys as it's near elastically isotropic. This study investigates the cold rolling deformation texture of polycrystalline tungsten using RS model, in which the stress and strain consistence is realized simultaneously. The texture evolution and effects of deformation parameters, including external as well as internal reaction stress, strain and activation of different slip, on texture during rolling are discussed by comparing the simulated results and reported experimental results in literatures. The results show that, the cold rolling deformation texture could be simulated statistically based on RS model. The accumulation of each reaction stress is different. The up-limit of reaction stress σ'₁₂ is found to be medium, meaning that σ'₁₂ exerts important effect on texture evolution. Much lower accumulation level of σ'₁₃ as well σ'₂₃ is displayed, each of which within certain range contributes to the increase of different γ-fiber texture components. The effect of σ'₂₂ can't be ignored during rolling, especially in the case of obtaining {111}<110> texture. Regarding the deformation textures of tungsten rolled to true strains of −1.7 and −2.91, {001}<110> texture is strengthened with the increasing strain and becomes dominant, implying the easier activation of {112}<111> slip systems; γ-fiber texture is weakened at higher strain, and the formation of {111}<112> texture shows significant effect of surface shear stress σ₁₃, which is due to the nonnegligible surface friction when rolling at high temperature.