The technological properties of reinforcing bars include many items. Different requests can be made according to the characteristics of different products, such as ordinary reinforcing bars requesting to stop bending and reverse bending (reverse bending) experiments, and some prestressing steel requesting to stop repeated bending, changing and winding experiments.

　　一切這些實(shí)驗(yàn)的方式不同水平地模仿了資料在實(shí)踐運(yùn)用時(shí)可能觸及的工藝加工方式，如普通鋼筋需求彎鉤或彎曲成型，預(yù)應(yīng)力鋼絲有時(shí)需纏繞等，而其目的就是考核資料對這些特定塑性變形的極限接受才能，因此工藝性能也是對資料的塑性請求，且與上述延性（伸長率）請求是相通的，普通來說伸長率大的鋼材，其工藝性能也好。

　　All these experiments simulate the processing methods that the data may touch upon in practice, such as bending or bending forming of ordinary steel bar, winding of prestressing steel wire, etc. The purpose of these experiments is to check the data's ability to accept the limit of these specific plastic deformation. Therefore, the process performance is also a plastic request for the data and is related to the ductility (extension) mentioned above. Length) Requests are common. Generally speaking, steel with high elongation has good technological properties.

　　但是與拉伸時(shí)的單向受力狀態(tài)相比，工藝性能實(shí)驗(yàn)的受力狀態(tài)就復(fù)雜得多，試樣變形類型與大小則各向（軸向、徑向）不同，鋼材的組織構(gòu)造、晶粒大小、有害剩余元素含量特別是內(nèi)部和外表任何影響連續(xù)變形的缺陷如裂紋、夾雜等都可能影響和招致實(shí)驗(yàn)不經(jīng)過。所以在某種意義上，關(guān)于考核鋼材的質(zhì)量，能夠說工藝性能實(shí)驗(yàn)更為嚴(yán)厲。

　　However, compared with the unidirectional stress state under tension, the stress state of the process performance test is much more complex. The deformation type of the specimen is different from that of the specimen in all directions (axial and radial). The structure, grain size, harmful residual element content of the steel, especially any defects, such as cracks and inclusions, which affect the continuous deformation both inside and outside, may affect and cause the experiment not to pass through. Therefore, in a sense, it can be said that the process performance test is more rigorous to assess the quality of steel.

　　另外鋼筋的反向彎曲實(shí)驗(yàn)實(shí)質(zhì)上是一項(xiàng)應(yīng)變時(shí)效敏理性實(shí)驗(yàn)這是由于鋼水中普通都含有一定數(shù)量的游離氮（N），也稱剩余氮，含量過高時(shí)，可招致鋼材經(jīng)塑性變形后在室溫下脆化。

　　In addition, the reverse bending experiment of steel bar is essentially a strain-aging sensitivity experiment, which is due to the fact that the steel usually contains a certain amount of free nitrogen (N), also known as residual nitrogen. When the content is too high, the steel can be brittled at room temperature after plastic deformation.

　　由于鋼筋常常需彎曲成型以后運(yùn)用，曾經(jīng)產(chǎn)生了塑性變形，假如材性變脆，構(gòu)造就不能接受使鋼筋再產(chǎn)生塑性變形的外加荷載（如地震），所以目前國內(nèi)外都將反彎實(shí)驗(yàn)作為一項(xiàng)重要技術(shù)請求列入鋼筋規(guī)范，同時(shí)對鋼的氮含量予以限制（不超越0.012%）。

　　Because steel bars often need to be used after bending and forming, plastic deformation has been produced. If the material is brittle, the structure can not accept the additional load (such as earthquake) which causes plastic deformation of steel bars. At present, the reverse bending experiment is included in the steel bar code as an important technical request at home and abroad, and the nitrogen content of steel is limited (not exceeding 0.012%).

　　研討標(biāo)明，用于鋼的微合金化的一些元素如釩、鈦、鈮等，特別是釩與氮有極好的親和力，鋼中參加釩可有效分離自在氮，釩與氮的分離還能進(jìn)一步加強(qiáng)釩對鋼的強(qiáng)化效果，因而有些規(guī)范也注明“假如有足夠的與氮分離的元素存在氮含量能夠高出規(guī)范規(guī)則”。

　　The study shows that some elements used in microalloying of steel, such as vanadium, titanium, niobium, etc., especially vanadium and nitrogen have excellent affinity. Vanadium in steel can effectively separate free nitrogen. The separation of vanadium and nitrogen can further enhance the strengthening effect of vanadium on steel. Therefore, some codes also indicate that "if there are enough elements separated from nitrogen, the nitrogen content can be higher than the norms".