热处理温度对TC10钛合金棒材组织与性能的影响

以不同变形量热锻TC10钛合金棒坯,得到了直径50 mm的钛合金棒材.分别在780、790、800、810、820℃对TC10钛合金棒材进行固溶热处理(保温时间1h,空冷),研究了热处理温度对TC10钛合金棒材组织与性能的影响.研究结果表明,热锻变形量达到70％的TC10钛合金棒材呈现出良好的强度和塑性;在经过温度为8...     

钛合金的热处理强化与应用研究

本文详细介绍了钛合金的化学成分、性能和市场应用前景；着重论述了钛合金的热处理原理、强化机制、热加工工艺及热处理工艺。     

热处理在冷喷涂增材制造中的应用

作为一种固态沉积技术, 冷喷涂增材制造(CS-AM) 存在的主要问题是喷涂制备材料的塑性较差, 而后续热处理可以有效改善这一问题, 相关研究涉及冷喷涂 Cu、 Zn、Al、 铝合金、 Ti、 Ti6Al4V、 低碳不锈钢等金属涂层（材料）。本文概述了热处理对冷喷涂增材制造上述金属涂层（ 材料） 电阻率、 耐腐蚀性能以及力学性能的影响,为热处理在冷喷涂增材制造中的应用提供参考。     

热处理对Nd-Fe-B系合金磁性能和显微组织的影响

通过对Nd-Fe-B系合金在烧结后的一系列热处理,分析研究了造成热处理后磁性能和显微结构变化的原因。指出烧结后的热处理对不同成分合金的矫顽力会产生不同的影响,某些成分的合金易于通过热处理提高矫顽力,而另一些成分的合金则较为困难。     

Fatigue Life of Titanium Alloys Fabricated by Additive Layer Manufacturing Techniques for Dental Implants

Additive layer deposition techniques such as electron beam melting (EBM) and laser beam melting (LBM) have been utilized to fabricate rectangular plates of Ti-6Al-4V with extra low interstitial (ELI) contents. The layer-by-layer deposition techniques resulted in plates that have different surface finishes which can impact significantly on the fatigue life by providing potential sites for fatigue cracks to initiate. The fatigue life of Ti-6Al-4V ELI alloys fabricated by EBM and LBM deposition techniques was investigated by three-point testing of rectangular beams of as-fabricated and electro-discharge machined surfaces under stress-controlled conditions at 10 Hz until complete fracture. Fatigue life tests were also performed on rolled plates of Ti-6Al-4V ELI, regular Ti-6Al-4V, and CP Ti as controls. Fatigue surfaces were characterized by scanning electron microscopy to identify the crack initiation site in the various types of specimen surfaces. The fatigue life data were analyzed statistically using both analysis of variance techniques and the Kaplan-Meier survival analysis method with the Gehan-Breslow test. The results indicate that the LBM Ti-6Al-4V ELI material exhibits a longer fatigue life than the EBM counterpart and CP Ti, but a shorter fatigue life compared to rolled Ti-6Al-4V ELI. The difference in the fatigue life behavior may be largely attributed to the presence of rough surface features that act as fatigue crack initiation sites in the EBM material.     

航空用高强度结构钛合金的研究及应用

对航空领域广泛使用的高强度结构钛合金Ti—15—3(TB5)，β21S(TB8)，Ti—1023(TB6)和BT22(TC18)的研究现状进行了综合评述和对比分析。     

热处理工艺对TA5钛合金棒材显微组织及性能的影响

经过多火次锻造得到具有均匀细小等轴组织的TA5钛合金棒材,在600~800℃范围内对其进行不同温度和不同保温时间的退火热处理,研究不同热处理工艺对其显微组织与力学性能的影响。结果表明,热处理温度在700~750℃,保温时间在60~90 min之间时,得到的组织为更加均匀的等轴组织;棒材的抗拉强度为740 MPa左右,屈服强度在595 MPa左右,延伸率在14%左右,强度和塑性达到较好的匹配。     

Use of Calcium in Alloys: From Modifying to Alloying

Calcium is one of the most widespread and, consequently, low-cost metals on Earth. It has been applied for a long time in modifying and alloying alloys of heavy metals, in particular, lead and copper. It is used as a modifier in cast irons and steels. Calcium began being applied for alloying light alloys based on aluminum and magnesium comparatively recently. In this review, the application fields of metallic calcium and its influence on the structure and properties of various alloys are considered. Alloys based on aluminum–calcium eutectic have been systematically investigated over last few years, and it has been established that they possess casting properties no worse than these of silumins, and they can be hot-rolled and cold-rolled with a high degree of deformation. Ternary and more complex phase diagrams of systems including calcium are constructed and multicomponent alloys based on them are investigated. All these circumstances make it possible to outline several groups of new promising Ca-containing aluminum alloys: (i) alloys hardening without quenching due to the isolation of nanodimensional particles of Al₃Zr, Al₃Sc, and Al₃(Zr,Sc) phases; (ii) high-strength alloys alloyed with traditional hardening elements of the aluminum solid solution, such as zinc and magnesium; and (iii) composite alloys having more than 20% eutectic intermetallic compounds in the structure. All these materials have reduced density, an improved set of operational properties, increased corrosion resistance, and high manufacturability when producing cast and deformed half-finished products.     

热处理对TC18钛合金丝显微组织与力学性能的影响

研究了热处理对TC18钛合金丝材显微组织与力学性能的影响。研究结果表明,对于多道次热拉2.0 mm丝材,随着退火温度由760℃升高至820℃,显微组织明显发生了再结晶和晶粒长大过程,并且α相含量显著减少,β相含量显著增多。随着温度的升高,抗拉强度呈明显下降趋势,由760℃时的1 110 MPa下降到820℃时的970MPa。在760℃退火时,保温时间由0.5 h延长到1.5 h,丝材的显微组织晶粒略有长大,力学性能略有降低。     

热处理工艺对Ti53311S钛合金组织与性能的影响

研究了低温退火和高温淬火＋时效两种热处理方式对Ti53311S钛合金棒材显微组织与力学性能的影响。实验结果表明：经两种不同热处理制度处理后,均能获得满足Q／XB1517—1998标准要求的Ti53311S钛合金棒材。经650oC低温退火处理后可获得等轴a＋β组织,经高温淬火＋时效处理后可获得等轴初生a＋含针状a的转变β双态组织。在生产中,可根据实际情况选取更为适宜的热处理方式,其中,较为经济的热处理方式为650℃×60min／AC;可获得较好力学性能的热处理方式为980℃×（30～90）min／WQ＋650℃×6h／AC。     

Recent Developments in Heat Treatment of Beta Titanium Alloys for Aerospace Applications

Beta titanium (β-Ti) alloys have been a subject area of intense interest since 1980s. By virtue of their unique properties, β-Ti alloys very well compliment the alpha and alpha + beta alloys. Heat treatment of β-Ti alloys is the crux to their technology and application. Over the last two decades, a number of researches have been carried out on issues related to heat treatment of these alloys—sub-transus solution treatment, duplex aging and heating rate to aging temperature. Improved understanding resulting from these studies has enabled designing optimum heat treatments to achieve refined microstructures free from deleterious features with improved mechanical properties under static and dynamic loading conditions. The purpose of this overview is to take stock of progress made in recent years in understanding the heat treatment of β-Ti alloys for a better commercial exploitation.     

热加工对Ti53311s钛合金显微组织和力学性能的影响

Ti53311s合金是一种适于550℃使用的耐热钛合金,本文对该合金在不同热加工条件下的显微组织进行了研究。结果表明,Ti53311s合金在β→α＋β转变温度以下,经单向拔长锻造的棒材的室温、高温性能与镦拔锻造的棒材相当。     

合金元素对Mg-Gd系合金组织及时效硬化行为的影响

利用扫描背散射电子像(SEM-BSE)和透射电子显微像(TEM)观察,研究了MgGd3,MgGd3Nd0.3和MgGd3Nd0.3Zn0.33种合金的铸态、固溶态显微组织结构,同时利用显微硬度仪研究了3种固溶态合金在200℃下的时效硬化行为。结果表明:3种合金经过520℃固溶处理后,均能使富稀土的初生相有效地固溶,形成可时效强化的过饱和固溶体合金。其200"C时效后峰值硬度的实现都源于基体中微细β’析出相的形成和弥散分布,而随后硬度随时效时间的变化趋势却有所不同。添加稀土元素Nd,有助于加快合金的时效响应。Nd和Gd共存时的析出强化使MgGd3Nd0.3合金在0～120 h时效阶段具有高于其他两种合金的硬度。过渡族元素Zn的添加,虽然使MgGd3Nd0.3Zn0.3的硬度相比MgGd3Nd0.3略低,但能够在长时间时效中保持硬度不明显下降。基于透射电镜观察,着重分析对比了在200"C 85 h时效条件下的3种合金的显微结构特征,讨论了添加Nd和Zn元素对析出相尺寸、形貌和分布特征的影响。     

Grain Refinement of Alloys in Fusion-Based Additive Manufacturing Processes

Metallurgical and Materials Transactions A - One of the less desirable aspects of fusion-based additive manufacturing is the propensity for coarse columnar grain structures crossing build layers to...     

TC11钛合金等轴组织热变形行为与组织演变

采用等温恒应变速率压缩试验研究了TC11钛合金等轴组织两相区980～800℃,应变速率O.001～O.1 s-1,变形程度50%条件下的变形行为,分析了变形参数对应力-应变曲线、微观组织演变机制和规律的影响,建立了该合金两相区变形的热加工图,并采用EBSD技术测试了热变形组织的晶界特征.结果表明:(1)980℃变形,β相是主要变形相,O.001～O.1 s-1之间的功率耗散效率值在动态回复和再结晶范围内;α相经历了变形促进下的溶解(高应变速率)和聚集粗化(低应变速率)的过程,即α晶粒尺寸和相含量随着应变速率的加快明显减小.(2)950～900℃变形,O.001～O.01 s-1之间的功率耗散效率值在超塑性变形范围内;变形主要是软基体的β相和界面的变形行为;变形过程中,α晶粒尺寸和相含量基本不变.(3)850～800℃变形,α相是主要变形相,发生了连续动态再结晶过程;β相起晶界协调变形的作用.     

Modeling and Monitoring of the Effect of Scan Strategy on Microstructure in Additive Manufacturing

Metallurgical and Materials Transactions A - Laser powder bed fusion is an additive manufacturing process that uses a selective melting technique to build three-dimensional metal structures. This...     

Ti对大线能量焊接焊缝组织和性能的影响

对不同Ti含量的气电立焊焊缝组织及力学性能进行了对比研究。结果表明,Ti的质量分数在0.028%~0.038%范围内时,焊缝中获得大量细小的针状铁素体,焊缝组织及低温韧性得以明显改善。当Ti过量时,焊缝中的针状铁素体减少,组织以贝氏体为主,低温韧性相应下降。焊缝组织中观察到块状和条状的M-A组元,随着焊缝Ti含量增加,其总量增加。焊缝夹杂物多为以氧化物为核心,外层包裹着MnS的复合夹杂物,并随夹杂物Ti含量的增加,由Mn-Si-Al-O型向Ti-Mn-Al-O型转变,有利于促进针状铁素体形成。而当焊缝中Ti过量时,主要夹杂物又转变为对针状铁素体形核无效的Ti-Al-O型,促进了贝氏体转变。     

Influence of Deformation and Heat Treatment on the Microstructure and Properties of High-Strength Low-Alloy Steel with Boron

The microstructure, fine structure, and mechanical properties of high-strength low-alloy steel with boron are studied after two different rolling technologies: (1) high-temperature hot rolling; (2) two-stage controlled rolling with accelerated cooling and subsequent quenching with tempering. The tempering temperature corresponding to irreversible tempering brittleness of the first kind is established. The reasons for embrittlement at that temperature are analyzed.