Q550D河南舞阳钢铁钢板定轧，材料厚度以及宽度可按照特殊要求倍尺下料

Q550D钢的牌号解析：一、Q550D表示方法：“Q”作为钢的屈服强度的“屈”字汉语拼音首位字母；“550”作为屈服强度数值，单位MPa；D—质量等级为D级（质量等级分为C,D,E）。二、Q550D当客户需要在钢板具有厚度方向性能时，则在上述规定的牌号后加上代表厚度方向（Z向）性能级别的符号，例如：，，。三、Q550D执行标准：GB/T ；GB/四、Q550D主要化学成份：牌号其它Q550D≤0.181.00～1.60≤0.55≤0.030≤0.030≥0.015适量a、碳（C）：钢中含碳量增加，屈服点和抗拉强度升高，但塑性和冲击性降低，当碳量0.23%超过时，钢的焊接性能变坏，因此用于焊接的低合金结构钢，含碳量一般不超过0.20%。碳量高还会降低钢的耐大气腐蚀能力，在露天料场的高碳钢就易锈蚀；此外，碳能增加钢的冷脆性和时效敏性。  b、硅（Si）：在炼钢过程中加硅作为还原剂和脱氧剂，所以镇静钢含有0.15－0.30%的硅。如果钢中含硅量超过0.50-0.60%,硅就算合金元素。硅能显著提高钢的弹性极限，屈服点和抗拉强度，故广泛用于作弹簧钢。在调质结构钢中加入1.0－1.2%的硅，强度可提高15－20%。硅和钼、钨、铬等结合，有提高抗腐蚀性和抗氧化的作用，可制造耐热钢。含硅1－4%的低碳钢，具有极高的导磁率，用于电器工业做矽钢片。硅量增加，会降低钢的焊接性能。c、锰（Mn）：在炼钢过程中，锰是良好的脱氧剂和脱硫剂，一般钢中含锰0.30－0.50%。在碳素钢中加入0.70%以上时就算“锰钢”，较一般钢量的钢不但有足够的韧性，且有较高的强度和硬度，提高钢的淬性，改善钢的热加工性能，如16Mn钢比A3屈服点高40%。含锰11－14%的钢有极高的耐磨性，用于挖土机铲斗，球磨机衬板等。锰量增高，减弱钢的抗腐蚀能力，降低焊接性能。  d、磷（P）：在一般情况下，磷是钢中有害元素，增加钢的冷脆性，使焊接性能变坏，降低塑性，使冷弯性能变坏。因此通常要求钢中含磷量小于0.045%，优质钢要求更低些。  e、硫（S）：硫在通常情况下也是有害元素。使钢产生热脆性，降低钢的延展性和韧性，在锻造和轧制时造成裂纹。硫对焊接性能也不利，降低耐腐蚀性。所以通常要求硫含量小于0.055%，优质钢要求小于0.040%。在钢中加入0.08-0.20%的硫，可以改善切削加工性，通常称易切削钢。五、Q550D力学性能牌号规格mm屈服度MPA抗拉度MPA伸长率 %－20℃冲击Akv? J 纵向Q550D≤50≥～830≥16≥40六、Q550D冶炼方法：钢由转炉或电炉冶炼，必要时加炉外精炼。 七、Q550D交货状态：Q550D钢板通常以调质状态交货。八、Q550D钢板主要用途：主要应用于重要的（低温）高强度结构件、工程机械、矿山钢结构件等。

of of Q550D steel:

1. Q550D : "Q" is the first of the "qu" as the yield of steel;"550" is the yield unit MPa;D - grade is D ( grade C,D,E).

When the needs to have the of the steel the the (Z ) level shall be added after the above such as: .

Iii. Q550D : GB/T ;GB/

Iv. Q550D Main :

Grade C Mn Si P S Al

Q550D ≤0.18 1.00 ~ 1.60 ≤0.55 ≤0.030 ≤0.030 ≥0.015

A, (C) : in steel yield point and but and . When 0.23%, the of steel will worse. the of low alloy steel used for does not 0.20%.High will also the of high steel in the open field is easy to rust;In can the cold and aging of steel. 

B. (Si) : is added in the as agent and so the steel 0.15-0.30% .If steel more than 0.50-0.60% is an . is used in steel it can the yield point and of steel.The of steel can be by 15-20% by 1.0-1.2% .The of and and can the and and make heat steel.Low steel 1-4%, with high used in the as steel sheet.The of will the of steel.

C, (Mn) : In the of is a good and . steel 0.30-0.50%.When 0.70% or more in steel is as " steel". with steel steel not only has but also has and so as to the of steel and of steel. For 16Mn steel is 40% than A3 yield point.Steel 11-14% has high wear and is used for ball mill etc.The of the of steel and the . 

D. (P) : In is a in which the cold of makes the the and makes the cold worse. the in steel is to be less than 0.045%, and the for steel is lower. 

E, (S) : is also a .It the steel to hot the and of the and and . is also bad for . the is to be less than 0.055% and 0.040% for high steel.The of 0.08-0.20% to steel which is often free steel.

V. of Q550D

Mm yield MPA MPA % -20℃ Akv?J

Q550D ≤50 ≥550 670 ~ 830 ≥16 ≥40

Vi. Q550D : Steel is by or and the if . 

Q550D : The Q550D steel plate is in the state.

Main USES of Q550D steel plate: used in (low ) high steel etc.