What are the differences in the properties of Q245R after normalizing?

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Q245R is a national standard container plate, where Q is the first letter of the pinyin for \"yield\". 245-Yield strength value. R: The first letter of the Pinyin for “rong” in Chinese. Niobium, vanadium, and titanium can be added to Q245R steel, and their contents should be specified in the quality certificate. The total content of these three elements shall not exceed 0.050% each; for example, grades such as 20R, 16MnR, 14Cr1MoR, 15CrMoR, 09MnNiDR, 12Cr2Mo1R, 16MnR(HIC), 20R(HIC), etc. fall into this category. These are the commonly used grades in China; there are also foreign grades, such as SA516Gr60, SA516GR70, etc. I. Chemical composition of Q245R
Grade | Chemical elements (mass fraction)/% | C | Si | Mn | Cr | Ni | Mo | Nb | V | P | S | Alt
Q245R | ≤0.20 | ≤0.35 | 0.50–1.00 | ≤0.025 | ≤0.015 | ≥0.020

Steel plate thickness/mm | Tensile strength R/(N/mm) | Yield strength R/(N/mm) | Elongation A/% | Temperature/℃ | Impact energy KV2/J
180° bending test | Bending diameter (b≥35mm) | 3–16 | 400–520 | ≥245 | ≥25 | 0 | ≥31 | d=1.5a
>16–36 | 400–520 | ≥235 | ≥25 | 0 | ≥31 | d=1.5a
>36–60 | 400–520 | ≥225 | ≥25 | 0 | ≥31 | d=1.5a
>60–100 | 390–510 | ≥205 | ≥24 | 0 | ≥31 | d=2a
>100–150 | 380–500 | ≥185 | ≥24 | 0 | ≥31 | d=2a

II. Standards applicable to Q245R: 20R and 20G. The previous process standards were GB6654 and GB713-86. Q245R is a newer grade, with the standard being GB713-2014. In fact, these two represent the same material; only the names differ. III. Q245R has special compositions and properties; it is primarily used for manufacturing pressure vessels. Depending on the application, temperature requirements, and corrosion resistance needs, different material grades for vessel plates should be selected. IV. The delivery conditions for Q245R are: hot-rolled, controlled rolling, and normalized. Flaw detection is added upon agreement between the supplier and the buyer.